David Hartley’s Enlightenment Psychology From Association to.docx

David Hartley’s Enlightenment Psychology: From Association
to
Sympathy, Theopathy, and Moral Sensibility
Richard T. G. Walsh
Wilfrid Laurier University
In Observations on Man, His Frame, His Duties, and His
Expectations David Hartley
(1749/1971) presented a systematic, comprehensive, complex,
and medically informed
psychological treatise, drawn from Newtonian mechanics.
Evidently motivated by
religious beliefs about the perilous state of humankind, he
speculated that human
nature’s physical foundation in vibrations and association
ranged from sensory pro-
cesses and simple ideas to sympathy (i.e., benevolent social
relations, leading to
perspective-taking), theopathy (i.e., loving union with God),
and moral sensibility (i.e.,
reliance on moral principles to guide conduct). However,
typical accounts of scientific
psychology’s roots in Enlightenment thought have neglected the
complex psycholog-
ical processes and developmental, interpersonal, societal,
religious, and moral aspects
of Hartley’s system. For him, manifestations of sympathy,
theopathy, and moral
sensibility are central to human experience, whereas self-
fulfillment results from the
developmental transit of self-interest to moral sensibility. Thus,

after describing the
multiple facets of association in sensation, ideas, action,
language, and memory, I show
how Observations synthesizes contemporaneous scientific,
religious, and moral thought
about human psychology. Then I relate Hartley’s views to
subsequent psychological
thought, identify parallels with concepts in past and present
scientific psychology, and
suggest the value of his synthesis for exploring the interface
between psychology, and
religion and spirituality. However, philosophical impediments
in psychology’s tradi-
tions make such explorations unlikely without facilitative
institutional changes.
Keywords: David Hartley, associationism, psychology and
religion, philosophical
psychology, history of psychology
According to E. G. Boring’s (1950) history of
experimental psychology, David Hartley
(1705–1757) elaborated the seminal concept of
association in his 1749 work, Observations on
Man, His Frame, His Duties, and His Expecta-
tions. Boring attributed scientific psychology’s
intellectual foundation to association as prac-
ticed by many Anglo American psychologists.
Hartley is also credited with producing in Ob-
servations “the first distinctly psychological
treatise” (Walls, 1982, p. 260), based on the
mechanistic assumptions of the Scientific Rev-
olution. Yet if textbooks of psychology’s his-
tory include Hartley, they typically do not de-
scribe how he construed association not just

mechanistically but also in terms of social, re-
ligious, and moral development, which
stemmed from both his medical practice and his
approach to Christianity. In Volume I of Obser-
vations, Hartley (1749/1971) discussed biolog-
ical, psychological, and social development pri-
marily, while integrating extant Christianity and
natural and social philosophy with conceptions
of self-interest and moral sensibility (also
termed “the moral sense”). In Volume II he
argued for the existence of God, prescribed so-
cial morality for humankind, and identified the
terms of universal eternal life.
In effect, Hartley integrated biophysical, psy-
chological, developmental, social, and religious
aspects of human nature (Allen, 1999, 2013).
His scope was biophysical in positing neurolog-
ical “vibrations” (internal physical responses
produced by sensory impressions) that operated
in tandem with association (Webb, 1988). His
scope was psychological in explaining associa-
tion as the catalyst for the relationship between
This article was published Online First August 29, 2016.
Correspondence concerning this article should be ad-
dressed to Richard T. G. Walsh, Department of Psychology,
Wilfrid Laurier University, Waterloo, ON, N2L 3C5, Can-
ada. E-mail: [email protected]
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Journal of Theoretical and Philosophical Psychology © 2016
American Psychological Association
2017, Vol. 37, No. 1, 48 – 63 1068-8471/17/$12.00
http://dx.doi.org/10.1037/teo0000047
48
perception and action. It was developmental in
incorporating biopsychosocial growth across
the life span, such as the emergent relationship
between language and thought. Hartley’s scope
was social in accounting for interpersonal and
societal relations. It was religious in positing the
ultimate annihilation of the self in both sympa-
thy (i.e., benevolent social relations leading to
perspective-taking) and theopathy (i.e., the per-
fectibility of humans in loving union with a
divine being). Ultimately, Hartley’s scope was
moral. Accordingly, his treatise has been char-
acterized as “one of the great [psychological]
syntheses of the eighteenth century” (Robinson,
1995, p. 271). Mindful that the overarching
purpose of Hartley’s (1749/1971) Observations
was to substantiate belief in God’s existence
and strengthen moral conduct (Allen, 1999,
2013), I discuss its psychological, religious, and
moral facets in the context of scientific, social,
and religious Enlightenment thought. Then I
compare it to subsequent and modern psycho-

logical thought.
Hartley structured Observations as a formal
logical argument with specific propositions. Ac-
cordingly, when quoting from the edition that I
consulted, I identify the volume and proposition
numbers before the page numbers because of
differences in pagination across editions.
Philosophical and Religious Roots
Hartley was an English physician with a mas-
ter’s degree but not a medical degree (Allen,
1999, 2013). With a colleague he conducted
research on kidney stones, from which he suf-
fered chronic severe pain. Attracted to practical
applications of science, known then as natural
philosophy, he was enamored of mathematics
and emergent statistics. Although his father was
an Anglican pastor, Hartley became an outspo-
ken, nonconforming Christian idealist. Thus, his
standpoint in Observations was rooted in both
natural philosophy and religion.
Philosophical Heritage
Examination of Observations reveals the her-
itage of Hartley’s Enlightenment forebears,
Isaac Newton (1642–1727), John Locke (1632–
1704), and George Berkeley (1685–1753).
Newton’s and Locke’s Influence
Broadly speaking, Newton’s mechanistic
conception of the universe as matter in motion
is one foundation for Hartley’s (1749/1971)

psychological system, including its religious
and moral aspects (Allen, 1999, 2013). Accord-
ing to Newtonian theory, matter is composed of
atomic particles cohering into molecular sys-
tems of attraction, repulsion, and motion grav-
itating toward Earth. As Newton had described
the reciprocal influence of these mechanistic
forces underlying the physical universe, so
Hartley deduced his conception from Newton’s
hypothesis of vibrations operating in sensation
and motion and proposed interacting laws of
vibrations and association underlying bodily
and mental functions.
Like Locke, whom he often cited in Obser-
vations, Hartley held that just as mechanical
laws govern natural objects, composed of at-
oms, so they govern the component particles of
human bodies (Allen, 1999). He also followed
Locke in adopting Newton’s view that one ac-
cesses the mind only through sensory impres-
sions and Locke’s explanation of habits as as-
sociation. But unlike Locke, he focused on the
mind/body problem, uniting physiological and
psychological phenomena and situating con-
sciousness in processes of the brain stem.
Yet Hartley’s psychological system also is
dynamic in that he adopted Newton’s principle
that reciprocal forces of attraction and repul-
sion, which shift between concretion and disso-
lution, are inherent in all natural objects, includ-
ing minute particles (Allen, 1999, 2013).
Besides mathematics and physics, Newton had
studied the relationship of natural philosophy,
morality, and law to divine wisdom (Westfall,

1980). Newton’s explorations of this relation-
ship apparently inspired Hartley to provide an
account of human psychology based on an an-
alogue to the Newtonian principle of reciproc-
ity. In effect, Hartley’s analogy was: attraction
is to association and concretion as repulsion is
to counterassociation and dissolution. Just as
the forces of repulsion are as necessary as those
of attraction, he reasoned, so the countervailing
forces of pleasure and pain, associations and
counterassociations, are in balance. His overar-
ching intention in Observations was to show the
operation of “a divinely preordained moral or-
49HARTLEY’S ENLIGHTENMENT PSYCHOLOGY
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der” both in psychological processes (Danziger,
2008, p. 46) and an ideal social order.
Berkeley ’s Influence
As a bishop in colonial Ireland, Berkeley
endeavored to preserve the relationship between

the Anglican state religion and a society threat-
ened by sociopolitical and intellectual develop-
ments (Leary, 1977). He strove to counter the
danger that materialist natural philosophy posed
to faith in immaterial reality, an immortal soul,
and an omniscient, benevolent God. Material-
ists held that, even if God created nature, He
(sic) was peripheral; nature functioned mecha-
nistically; and all natural objects, including hu-
mans, were explicable only materially. Conced-
ing material reality exists, Berkeley viewed it is
a mental product and God as the origin of ideas.
Representing the only certainty for Berkeley,
ideas encompass sensing, perceiving, imaging,
and thinking, and constitute all natural objects.
In addition, Berkeley argued that just as nat-
ural objects are attracted to each other through
gravity, so humans are naturally sociable
(Leary, 1977). Social harmony, anchored by the
existing class structure, requires order, duty,
and virtue (Kelly, 2005), whereas self-centered
desires expressed in greed and display of wealth
impair the common good (Leary, 1977). For
Berkeley, individuals act morally by exercising
rational free will (Darwall, 2005). A benevolent
God requires that humans conform to His will
by obeying his earthly representatives, namely
clergy and the sovereign, who administer di-
vinely sanctioned religious and secular laws.
Apparently, Hartley (1749/1971) adopted
much of Berkeley’s thought. He too held that an
active mind renders sensory experience mean-
ingful with perceptual categories that direct hu-
man action. Employing the term “frame” to

mean anatomical and physiological composi-
tion, Hartley stated, “The internal frame of our
minds [is] the source and spring from whence
our external actions flow” (Vol. II, prop. 71, p.
326). Like Berkeley, he proposed that touch and
kinesthetics link perception with action (Allen,
2013).
However, Hartley insisted that the term
“mind” encompasses all physiological and psy-
chological phenomena. Consciousness, he pos-
ited, results from the mechanistic laws of vibra-
tions and association. Moreover, animals,
depending on the species, have some level of
consciousness, the essential difference with hu-
mans being anatomical (Allen, 2013). As parts
of nature, matter and spirit simultaneously con-
stitute humans; thus, Hartley rejected belief in a
separate, immaterial mind/soul. Although his
acquaintance with them is unknown, French
peers Denis Diderot (1713–1784) and Julien La
Mettrie (1709 –1751) also argued that the mind/
soul is based materially in the brain (Walsh,
Teo, & Baydala, 2014). Still, Hartley believed
in the soul’s potential for eternal life with God
and was deeply troubled by social and moral
decay.
Free Will
The notion of a rational will guiding the mind
to take specific actions was central in Berk-
eley’s, Thomas Reid’s (1710 –1796), and Im-
manuel Kant’s (1724 –1804) metaphysics, as
well as in Christian theology (Royce, 1961).

But for Hartley (1749/1971), “the seat of the
soul” is the brain, which operates mechanisti-
cally (Vol. I, prop. 21, p. 110); therefore, vibra-
tions are the basis of ideas and voluntary motion
or will. Hartley recognized the operations of
“practical freewill,” but claimed “it results from
the frame of our natures” (Vol. I, p. viii). The
expression, “an act of will,” he asserted, is an
inaccurate attribution to a mechanistically ex-
plicable situation, the result of an associatively
produced motive. In his words, “The will is
therefore that desire or aversion [that] is stron-
gest for the present time” (Vol. 1, prop. 89, p.
371).
In critiquing free will Hartley (1749/1971)
distinguished between “popular” language,
meaning oral and written discourse in which
humans speak or write about what we intend to
do or not, and “philosophical” language, mean-
ing recognition that any presumed voluntary
action is “excited by an associated circum-
stance” (Vol. I, prop. 70, p. 235). It is “popular”
language, he maintained, that implies that we
can choose actions because of free will. Al-
though popular language is appropriate in its
domain, it is not equivalent to “philosophical
necessity,” for which the “doctrine of associa-
tion” is the scientific basis, he argued. Thus, in
the Conclusion to Volume I, Hartley (1749/
1971) reasserted a mechanistic foundation for
“free will in the philosophical sense” (p. 501).
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Nevertheless, Hartley appealed to divine neces-
sity as the ultimate explanation for human con-
duct: “Man is subject to a necessity ordained by
God” (p. 508), given that we “are what we are
entirely by the grace and goodness of God” (p.
510), known in the form of a benevolent Father
God. Moreover, as he asserted later, the moral
sense monitors one’s conduct.
Philosophical Reflection
Hartley adhered to the Newtonian proposi-
tions of universal necessity and the certainty of
cause-and-effect relations. This “doctrine of ne-
cessity” or “necessitarianism” meant that just as
an absolute God bent the physical world to His
(sic) will, so humans as God’s biological cre-
ations follow it by necessity (Swartz, 1985).
Consequently, the laws of physics determine the
laws of body and mind that, in turn, mirror the
structure of the natural world and the harmonies
of the universe, revealing a divine system of
moral governance. In this regard, Hartley’s syn-
thesis seems to reflect idealism. Thus, his claim

that “virtue has always the fairest Prospect,
even in this Life; and Vice is always exposed to
the greatest Hazards” (Vol. II, prop. 79, p. 363)
suggests Gottfried Leibniz’s (1646 –1716) opti-
mistic faith in a benevolent God and benign
world that Voltaire (1694 –1778) satirized
(Walsh et al., 2014). In addition, echoes of
natural and revealed religion reverberate
throughout Observations.
Religious Heritage
In Hartley’s context the prominent systems of
religious beliefs were religious revivalism, de-
ism, and revealed religion (Hirst, 2005). Angli-
can Christianity was (and remains) the state
religion, which like other revealed religions,
provides its adherents with explanations of mat-
ters of faith and morals based on what revela-
tion (i.e., personal experience and scripture,
subject to interpretation by religious authorities)
shows about God, human nature, and moral
conduct.
Religious revival movements, such as the
Philadelphian Society, emphasized the practice
of benevolence, love, peace, and piety (Hirst,
2005). Hartley’s concepts of sympathy and
moral sensibility coincide with the revivalist
notions of benevolence and peace and the Uni-
tarian stress on agape (i.e., fraternal and sororal
love), but Observations is not laced with reviv-
alism per se.
Among natural philosophers and their devo-

tees deism was common. Deists believe that
empirical observation and logical argument, ex-
clusive of revelation, are sufficient to establish
the existence of a God who set nature in motion
and let it be (Gay, 1968). Deism relies on what
natural religion, grounded in empirical reality
and reason, shows about God, human nature,
and moral conduct. Thus, for Hartley (1749/
1971), natural law dictated how the universe
and human nature function. He argued, “Since
God is the cause of all things . . . he must be the
cause of all the motions in the material world”
(Vol. II, prop. 6, p. 31). Moreover, during his
era a nascent counterpoint to religion consisted
of indifference to religion as well as agnostic
and atheistic discourses in English society
(Fairchild, 1942). Perhaps Hartley sought to
counter this cultural strain with a religiously
inspired but scientifically grounded explanation
of human nature, known as religious material-
ism, that fused natural philosophy with natural
religion.
Nevertheless, his persistent exhortation for
society to return to God shows the influence of
revealed religion, specifically Anglican con-
cepts. Hartley (1749/1971) affirmed faith in
“the existence and attributes of God, his provi-
dence, a future state [an afterlife], and the re-
wards and punishment of it” (Vol. I, prop. 76, p.
347). He echoed the doctrine of universal sal-
vation by which fallen humanity will become
reconciled with God through the Second Com-
ing of Christ and will return to Eden, the Garden
of Paradise. Believers thereby will “become
members of the mystical body of Christ; all have

an equal care for each other; all increase in love
and come to their full stature, to perfect man-
hood [sic]” (Vol. II, prop. 68, p. 287, emphasis
in original).
Hartley (1749/1971) also held a virtually
apocalyptic vision of the human condition, ex-
claiming in the penultimate sentence of the
Conclusion to Volume II, “The present circum-
stances of the world are extraordinary and crit-
ical, beyond what has ever yet happened” (Vol.
II, p. 455). In this section he lamented the
practice of “Christian countries of Europe” (p.
441) turning their backs on ideals of the faith.
He claimed that a “torrent of vice and impiety
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. . . seem ready to swallow us up” (p. 440)
because of the following, interconnected reli-
gious and societal dangers that “threaten ruin
and destruction to the present states of Chris-
tendom” (p. 441): atheism and infidelity to

Christianity, male and female lewdness, civic
administrators’ self-interest, contempt for hu-
man and divine authority among the inferior
classes, clergy’s obsession with worldly mat-
ters, and careless education of youth and their
consequent corruption.
Reflection on Religious Roots
It appears that Hartley was convinced that
only by adopting a religiously but scientifically
sound, psychological synthesis could human-
kind secure salvation. In Observations he at-
tempted to provide a plausible rationale for ob-
jectively regarding the natural world as a
reflection of divine laws. He understood the
person as explicable by those laws and as in-
tended for salvation in eternal union with God,
pending ethical conduct. As such, Hartley’s
standpoint evinces both revealed and natural
religion. But it is not theological per se.
Hartley’s Psychological System of Thought
In 99 propositions in Volume I of Observa-
tions and 95 in Volume II, Hartley (1749/1971)
explained psychological functions in terms of
the complementary “laws” or “doctrines” of
vibrations and association. Vibrations explain a
person’s frame and cause association, whereas
association explains mental capacities in rela-
tion to developmental and social processes. Vi-
brations and association are “subject to the laws
of mechanism . . . [i.e., body and mind have] a
mechanical nature” (Vol. I, prop. 78, p. 267),
while “all reasoning, as well as affection [i.e., a

hierarchy of passions], is the mere result of
association” (Vol. I, prop. 99, p. 499).
Proposing an inclusive system of psycholog-
ical dimensions that develop across the life
span, Hartley characterized all sensory, kines-
thetic, psychological, social, religious, and
moral action as reciprocally related, just as body
and mind are; hence, he cautioned, one can
investigate individual psychological phenom-
ena only artificially (Allen, 2013). Giving nu-
merous medical examples (e.g., phantom-limb
experiences), he addressed unconscious phe-
nomena that influence mental life (Richardson,
2001) as well as social, religious, and moral
development.
Basic Processes
To explain how basic psychological pro-
cesses occur in humans and animals, Hartley
accepted Newton’s hypothesis that physical im-
pulses vibrate. He reasoned that the spinal cord,
brain stem, and nerves collectively govern sen-
sations and movement, whereas the brain gov-
erns ideas. Hartley (1749/1971) assumed that
“since the human body is composed of the same
matter as the external world, it is reasonable to
expect that its component particles should be
subjected to the same subtle laws” (Vol. I, prop.
9, p. 62). He also argued that human action is
motivated by “obtaining pleasure and removing
pain” (Vol. I, prop. 22, p. 112). However, the
source of all good, he insisted, is God, who is
associated with all our pleasures. For Hartley,

the divine being is the ultimate cause of reality,
and the ultimate goal of human development is
union with it.
Sensation
According to Hartley, sensory impressions
evoke physical vibrations in the molecular par-
ticles of the nerves, the spinal marrow, and
ultimately the medulla. Vibrations occur as “vi-
bratiuncles,” (i.e., little vibrations), which are
positive and negative charges in the electro-
chemical transmission of impulses. As Har-
tley’s biographer explained, “A nerve fiber vi-
brates, changes its frequency or amplitude of
vibration, and transmits those changes to other
fibers” (Allen, 1999, p. 398). Sensory input
stimulates vibratiuncles traveling to the brain,
causing a response. For instance, a sound wave
evokes a vibration that one hears as a specific
tone. Moderate vibratiuncles produce pleasure,
violent ones produce pain. The nervous system
then “remembers” experiences of pleasure and
pain. Anything not a sensation is an “idea.”
The close relationship between an individu-
al’s sensations and actions, particularly skilled
actions, is the basis for the biophysical union of
vibratiuncles, which, Hartley (1749/1971) pro-
posed, “cohere together through joint impres-
sion, i.e., association” (Vol. I, prop. 11, p. 71).
In this respect he concurred with Berkeley that
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the perception of coherence is the result of ideas
generated by joint impression from the senses,
and that “the fundamental source of information
in respect of the essential properties of matter”
and “our first and principal key to the knowl-
edge of the external world” are embodied in the
sense of touch (Vol. I, prop. 30, p. 138).
Ideas
Concerning the relationship among physical
events, neurological processes, and psycholog-
ical phenomena, Hartley discussed how the
mind categorizes experience. Ideas represent
the mechanistic conjunction of vibratiuncles
and association. Just as the concepts of vibra-
tions and vibratiuncles explain sensations of the
body, so association explains processes of the
mind. Designated collectively as ideas, associ-
ation encompasses perception, movement,
memory, emotions, language, and cognition.
Although vibrations necessarily accompany
mental events through association, the latter
generates ideas and perfects secondarily auto-

matic actions.
Hartley (1749/1971) hypothesized that the
plethora of associative connections among
nerve fibers, expressed in physical sensations,
brings the brain to the verge of complex psy-
chological phenomena. An “attraction” exists,
he hypothesized, between sensory impressions
and simple ideas, motivated by pleasure-
seeking and pain-avoidance, analogous to how
gravity mechanistically and deterministically
binds physical bodies together. This psycho-
physiological attraction constitutes association,
Hartley speculated, in that interacting vibrati-
uncles within nerve fibers are transmitted to
other nerve fibers in connected webs of associ-
ation. These webs represent the active process
that engenders ideas that jell from aggregated
impressions.
Frequent repetition of simple sensations
leaves “images” of them that amalgamate to
form what Hartley (1749/1971) termed “simple
ideas.” These are “the individual and largely
imperceptible neural events that register sen-
sory stimuli” (Allen, 1999, p. 189). In turn, as
Locke (1690/1975) had held, aggregates of sim-
ple ideas become complex ones. Compounded
complex ideas then assemble into what Hartley
(1749/1971) termed “decomplex” ideas, such as
multifarious language. Thus, “Complex ideas
are our primary categories of perception, emo-
tion, and action,” whereas “decomplex ideas are
the sequences we form out of complex ideas”
(Allen, 1999, p. 189). Using his analogy, simple

ideas are like letters, complex ideas like words,
and decomplex ideas like sentences, whereas
the mind is a “hyper-complex” idea. Hartley
claimed that because sensations are corporeal,
ideas are as well. He illustrated this point by
asserting that association enables a person to
interpret the circumstances of suffering a bodily
wound.
Hartley explained complex psychological
processes as the eventual result of neuronally
associated, joint impressions, by which mean-
ingful perceptions emerge from sensory impres-
sions conveyed by two or more sensory modal-
ities simultaneously. Thanks to association,
every whole perception is greater than the sum
of its parts, to employ an anachronistic concept,
and coheres. Association connects sensations
with ideas in that cerebral vibrations run parallel
to mental events, whereas the latter are linked
with the internal feelings of sensations and ideas
(Walls, 1982). Hartley’s example was learning
to play the violin, when the interacting pro-
cesses of audition, vision, and kinaesthetic
movement, aided by self-monitoring, are in-
volved. At each level of learning, he posited, a
given psychological body–mind sequence func-
tions as a totality.
According to Hartley (1749/1971), just as
association arises from vibrations, so “most
complex ideas arise from sensation” (Vol. I,
prop. 83, p. 360), not from reflection, which
contradicted Locke’s position. Yet Hartley also
held that ideas can entail physiological and psy-
chological processes not derived immediately

and directly from sensations. Rather, they can
result from, using current terms, perceptual and
cognitive constructions. But regardless of their
origins, ideas for Hartley always occur in de-
velopmental processes and social contexts.
Action
In Hartley’s (1749/1971) synthesis motoric
action is central and results from the conjunc-
tion of vibrations and association. In his words,
If any sensation A, idea B, or motion C, be associated
for a sufficient number of times with any other sensa-
tion D, idea E, or muscular motion F, it will, at last,
excite d, the simple idea belonging to sensation D, the
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very idea E, or the very muscular motion F. (Vol. I,
prop. 20, p. 102, emphasis in original)
Mundane activity across the life span takes

the form of initiated, then practiced movements.
Giving the example of an infant learning to
grasp, Hartley explained how any movement,
sensation, or idea can excite associated move-
ments, sensations, and ideas in a stepwise fash-
ion. His term “automatic” describes involun-
tary, homeostatic physiological responses at the
basic level (e.g., pulse rate), caused by vibra-
tions (Allen, 1999). Reflexive action is the ori-
gin of semivoluntary and voluntary actions,
whereas motoric action and its control occur by
means of association. The perception of action
and ideas proceeds in the same way that sensa-
tion does. In sum, learning voluntary skilled
movements results from the union of motoric
vibrations, physical sensations, and correlated
ideas. To use modern psychological language,
automatic biological associations serve as stim-
uli for sensations, ideas, and motoric action that
become, in Hartley’s terms, “secondarily auto-
matic” or “voluntary.” Such action, including
spontaneous and improvised action, comprises
skilled movements. For instance, Hartley under-
stood the flexible actions of adept musicians
responding to the technical and interpretive de-
mands of musicianship as decomplex actions.
All told, association, triggered by substitutions
of the original stimulus, explains all voluntary
action, including sexual attraction and lan-
guage.
Language
Although, for Hartley, humans resemble
“brute creatures” in that the twin laws of vibra-
tions and association apply to all animals, lan-

guage makes humans distinct. We learn to
speak motorically on the basis of reflexes, he
claimed, then from the sounds we create and
those that we perceive and imitate. Mastery of
language occurs through joint impression (in
current terms, through perceptual categoriza-
tion). As we develop, we exercise conscious
control of complex actions (e.g., the motoric
actions involved in babbling) that become sec-
ondarily automatic and engage in decomplex
actions (e.g., comprehensible language) that
comprise clusters of complex actions. Associa-
tion triggered by listening, watching, and mak-
ing speech-like sounds produces ideas, which
are the result, not the cause, of language devel-
opment. However, Hartley asserted, the mean-
ing of any sentence derives from its entire con-
text, not from its component ideas, because
conveying a sentence occurs interpersonally
(Allen, 2013).
Although for Locke, language is analogous to
a dictionary and expresses ideas, for Hartley,
language is sensorily and motorically based ini-
tially, but then entails learning the rules for
making sequences of sounds acceptable within
a given culture (Allen, 2013). The biopsycho-
social action that constitutes language, then,
produces ideas, Hartley argued, rather than, as
Locke held, that ideas produce language. Only
association generates words and phrases, and
only words and phrases generate ideas. Hartley
explained that humans develop personal associ-
ations with particular words; for some listeners,
a speaker’s use of the term “greed,” for exam-

ple, elicits one connotation, whereas for other
listeners different connotations emerge.
According to Hartley (1749/1971), language
has two chief aspects: First, it proceeds from
automatic physiological motions to simple,
complex, and decomplex ideas operating under
voluntary control. Second, the association of
ideas is tied to decomplex motoric action, in-
cluding expressive language. Thus, “the decom-
plex idea belonging to any sentence is not com-
pounded merely of the complex ideas belonging
to the words in it” (Vol. I, prop. 12, p. 79)
additively. Rather, individuals derive meaning
from a complete linguistic expression—no mat-
ter its length—that captures decomplex ideas
always in relation to a particular interpersonal
context.
Memory
In Hartley’s (1749/1971) account of second-
arily automatic action, memory is pivotal
among psychological “faculties”: “All our vol-
untary powers are of the nature of memory”
(Vol. I, prop. 89, p. 381). Recalling an experi-
ence that seems like “yesterday” is the result of
“vividness of the clusters and their associations
corresponding to the nature of a recent event”
(p. 378). At the root, “Memory depends entirely
or chiefly on the state of the brain” (p. 374), and
“the most perfect memory is that which can
receive most readily and retain most durably”
(p. 381). In addition, the state of one’s memory
54 WALSH

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has ramifications: “No man [sic] can have a
strong judgment with a weak original power of
retaining and remembering” (p. 382).
For Hartley, memory is also connected with
“the passions.” Just as children achieve volun-
tary control over their bodily movements by
substituting for original associations, so in sit-
uations fraught with emotion a series of substi-
tutions (“transferences”) occurs that shapes per-
sonality. In this regard, Hartley gave an
example of potentially enduring, painful asso-
ciations and transferences formed by a child’s
fearful encounter with her or his inebriated fa-
ther. In keeping with Newtonian dynamics, for-
getting is as essential as remembering for Hart-
ley.
Intellectual Affections
Crucially in Hartley’s (1749/1971) synthesis
association serves as an adherent for the self,

social relations, and religious and moral devel-
opment. It does so, mediated by six sequential
classes of “intellectual affections” (“passions”)
that “can be no more than aggregates of simple
ideas united by association . . . or traces of the
sensible pleasures and pains [made up] by their
number and mutual influence upon one another”
(Vol. I, prop. 89, p. 368). Stemming from sen-
sation and ideas, enacted motorically, and con-
stituted in verbal and symbolic language and
memory, the affections are (1) imagination (i.e.,
perceiving human and nonhuman objects as
pleasurable or painful); (2) ambition (i.e., striv-
ing for status and approval from valued others);
(3) three types of self-interest, each entailing the
hedonistic principles of seeking pleasure while
avoiding pain: (a) gross (objects of one’s imag-
ination and ambition), (b) refined (objects of
one’s sympathy), and (c) rational (objects of
one’s theopathy, namely, the divine); (4) sym-
pathy; (5) theopathy; and (6) the moral sense,
which arises from sympathy and theopathy but
guides them.
Observing that an affection can be pleasur-
able or painful, depending on the situation,
Hartley (1749/1971) summarized the affections
as twofold: love and hatred. These biologically
based dispositions are manifest across the life
span as desire and aversion and are expressed
socioculturally as virtue and vice. The final res-
olution to the perpetual tension between the
reciprocal forces of virtue and vice, attraction
and repulsion, occurs during the Second Com-
ing, when reconciliation with Christ will occur,

enabled by mechanistic association.
Developmentally, according to Hartley
(1749/1971), “we do, and must, upon our
entrance into the world, begin with idolatry to
external things, and, as we advance in it,
proceed to the idolatry of ourselves” (Vol. II,
prop. 4, p. 22). Initially, then, the affections
of imagination and ambition prevail. We
adapt to pleasurable and painful experiences
by relying on gross self-interest that—to in-
sert an ahistorical psychoanalytic concept—
eventually exercises ego-functions to monitor
the demands of imagination and ambition. As
development unfolds, pleasure and pain trans-
fer from one class of affections to the next.
Ideally then, sympathy, theopathy, and the
moral sense prevail during adulthood. Al-
though the affections proceed mechanisti-
cally, they are rooted in association, not in
vibrations; hence, they are reciprocally influ-
ential. In Hartley’s (1749/1971) words, “As
sensation is the common foundation of all
these, so each in its turn, when sufficiently
generated, contributes to generate and model
all the rest” (Vol. I, prop. 89, p. 368).
Sympathy
As our social relations become more com-
plex, Hartley (1749/1971) argued, “the plea-
sures of sympathy improve those of sensation,
imagination, ambition, and self-interest by
limiting and regulating them” (Vol. I, prop.
68, p. 283). Growth from egocentric pursuit
of happiness to sympathy and allocentric be-

nevolence directed to everyone’s wellbeing
bridges the biological and transcendent as-
pects of human nature. It is God’s will, Hart-
ley believed, that inclines us to do good to
others. Rejoicing at others’ “happiness,” ex-
pressed in generosity and benevolence, or
grieving for their “misery,” expressed in em-
pathy and mercy, represents sympathy’s plea-
sures. Conversely, rejoicing at others’ misery,
expressed in jealousy and cruelty, or grieving
for their happiness, expressed in envy, repre-
sents sympathy’s pains. Assuming benign de-
velopment occurs, one’s “primary pursuits”
are sympathy and theopathy.
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Theopathy
For Hartley, theopathy meant the pleasures
and pains, love and fear, stimulated by contem-
plating God, the ultimate cause of all natural
objects and the object with whom we associate

our deepest pleasure. Accordingly, theopathy
represents the highest possible state; as Hartley
(1749/1971) put it, “the love of God affords a
pleasure which is superior in kind and degree to
all the rest of which our natures are capable”
(Vol. II, prop. 71, p. 311). “Theopathetic affec-
tions”—faith, fear, gratitude, hope, trust, and
resignation—are the basis of moral sensibility
from which we induce practical moral conduct,
culminating in loving God.
In Hartley’s synthesis, therefore, develop-
ment consummates in religious experience, ex-
pressed in sympathy, piety, and moral conduct,
yet motivated by the pursuit of pleasure, not by
reason. Thus, for him the highest form of
knowledge, including natural philosophy, is
natural and revealed religion. As Hartley (1749/
1971) explained, “The temper of mind pre-
scribed by religion, viz., modesty, impartiality,
sobriety, and diligence, are the best qualifica-
tions for succeeding in all inquiries” (Vol. I,
prop. 88, pp. 366 –367). Rather than a turning
away from empirical reality, therefore, theopa-
thy represents a turning into spiritual reality
(Allen, 1999).
Moral Sensibility
Earlier, Anthony Ashley Cooper, known as
Shaftesbury (1671–1713), advanced the concept
of moral sensibility (Billig, 2008). Against the
individualistic standpoint of his foster father,
Locke, he construed human nature interperson-
ally and promoted benevolence and virtue as the
organizing principles for living a moral life in

service to the common good and in accord with
a divinely and morally ordered universe. Hart-
ley expanded Shaftesbury’s perspective by sit-
uating moral sensibility as the guide for embod-
ied sympathy and theopathy. Assuming virtuous
action is associated with pleasure, Hartley af-
firmed that the pleasurable effects of past action
guide future action. But transcending hedonism,
he held that emerging capacities for expressing
imagination, personal ambition, and self-
interest shape our actions (Allen, 1999). As we
develop over the life span, individual desire
defers to sympathy, facilitated by what today is
known as perspective-taking. In Hartley’s
(1971/1749) words,
The rule of placing ourselves in the several situations
of all the persons concerned and inquiring what we
should then expect is of excellent use for directing,
enforcing, and restraining our actions and for begetting
in us a ready constant sense of what is fit and equitable.
(Vol. I, prop. 70, p. 294)
Moreover, sympathetic human relations orient
us to contribute to the common good, Hartley
argued. Accordingly, he admonished readers
against hedonistic living and indulging in pos-
sessions, because they contradict charitable re-
lations with the poor. In his synthesis, although
the intellectual affections remain secondary
pursuits, ideally they become transformed into
positive perceptions of others and the natural
world.
According to Hartley (1749/1971), all the

pleasures and pains of imagination, ambition,
self-interest, sympathy, and theopathy coalesce
within moral sensibility, leading “to the love
and approbation of virtue and to the fear, hatred,
and abhorrence of vice” (Vol. I, prop. 99, p.
497). At this apex of development, in full rela-
tionship with others and God, moral sensibility
enables the individual to moderate sympathy
and theopathy by, to credit Hartley’s notion,
annihilating the self. The moral sense elicits
sympathetic and theopathetic conduct, because
the aim of benevolence, piety, and rational self-
interest, Hartley (1749/1971) reasoned, is to
serve as “explicit guides of life in deliberate
actions” (Vol. II, prop. 74, p. 338). Practicing
benevolence and piety in conjunction with the
moral sense enables fully experiencing the plea-
sures of honorable human relations. Further-
more, such practice not only enhances gross
self-interest, but it is the sole means of securing
refined and rational self-interest.
However, Hartley acknowledged the poten-
tial for weak development of moral sensibility
and resultant negative content in sympathy and
theopathy. He also did not deny the power of
negative human passions and motives and rec-
ognized that behaving compassionately can be
tiresome, even nettlesome. No matter how
highly developed one’s moral sensibility might
be, the pains of sympathy are ever present, such
as rejoicing in the misery of others, deriving
pleasure from treating others malevolently,
56 WALSH

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grieving about others’ happiness, and experi-
encing pain from treating others benevolently.
In Hartley’s (1749/1971) words,
As we must forgo the pleasures of malevolence, so we
must patiently and resolutely endure the pains of be-
nevolence, particularly those of compassion. . .. In like
manner, theopathy, and the moral sense, are the occa-
sions of some pain, as well as of great and lasting
pleasure. (Vol. 1, prop. 68, p. 289)
Hartley’s belief that even, or especially, the
most fully developed persons struggle psycho-
logically with the capacity to do evil to others
seems similar to the existentialist views of So-
ren Kierkegaard (1813–1855) and Fyodor
Dostoevsky (1821–1881; Allen, 2013). But in
Hartley’s system the ultimate resolution to the
perpetual tension between the reciprocal forces
of good and evil, attraction and repulsion, oc-
curs during the final reconciliation with Christ.
Again, association is the mechanism that en-
ables this climactic transformation to occur.

In sum, Hartley’s (1749/1971) abiding inter-
est was to strengthen the association between
benevolence and pleasure and “to extinguish all
kinds and degrees of malevolence” (Vol. I,
prop. 69, p. 291). He maintained that the “rule
of life,” his term for how nature, created by
God, dictates how we should behave, favors
conformity with conventional Christian virtue,
not vice. The aim of this rule is to actualize
benevolent relations by practicing the principle
of loving others as ourselves. At the heart of
Hartley’s synthesis, identification with divine
purposes induces both moral conduct and hap-
piness. Moral sensibility integrates the inferior
classes of pleasure—sensation, imagination,
ambition, and self-interest—with the superior
classes of sympathy and theopathy, which are
essential for sustaining moral sensibility. How-
ever, he did not address how moral sensibility
might operate in relation to the subtle psycho-
logical functions of such hyper-complex ideas
as reflection and human action or how it differs
from free will.
The Self
In Hartley’s (1749/1971) system, the self is
subordinate to the moral sense in that associa-
tion is the basis for the sense of self, which
develops in a sociolinguistic context of emo-
tional memories of one’s intimate relationships
(Allen, 1999). Emotions, for Hartley, are ex-
pressed somatically in response to concrete cir-
cumstances. Emotions then generate by associ-

ation the self’s emergence, development, and
ultimate transcendence. The catalyst for the
self’s journey is the transference of emotions
from sensory vibrations of pleasure or pain to
associated perceptions of memories, verbal and
symbolic language, and hypothesized causes.
We learn to love what we approach and hate
what we avoid. In current terms, the stories we
tell about our experiences and the emotions we
ascribe to them shape our memories and per-
sonality.
According to Hartley, when we become more
able to love others, the self matures, but is only
transformed by a loving relationship with God
(Allen, 2013). Whereas the lower self is fulfilled
in rational self-interest, animated by imagina-
tion and ambition, the higher self is fulfilled in
moral sensibility, inspired by sympathy and the-
opathy. When we fully express the latter, we
experience “perfect self-annihilation and the
pure Love of God” (Vol. II, prop. 67, p. 282).
Identification with divine purposes, Hartley
posited, leads to moral conduct and happiness.
Self in Society
One foundation for Hartley’s (1749/1971)
psychological standpoint lay in the attributes of
the Judeo-Christian Father God, the truth of the
Hebrew and Christian Bibles as the literal
“Word of God,” and the superiority of Judeo-
Christianity, in descending order, to “Mahomet-
ans,” pagans, and savages. These beliefs con-
cerning one’s relations with society mirrored
extant patriarchal and paternalistic views of

gender relations and the social order.
Hartley (1749/1971) insisted that benevolent
“commerce between the sexes” requires con-
forming to conventional morality and gendered
social relations (Vol. II, prop. 53, p. 228). Al-
though he stated that “entire equality of the two
sexes” occurs when the “love [between husband
and wife] is mutual and perfect,” men possess
“greater bodily strength and firmness of mind”
than women (Vol. II, prop. 70, p. 301), which
was the consensus in his era. Yet he deviated
from the social norm by promoting the view that
“the Negro nations” descended from the same
Biblical ancestors as “Europeans” (Vol. II,
prop. 24, p. 109, emphasis in original).
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Regarding the social order, Hartley (1749/
1971) urged inferiors to obey “the civil magis-
trate” (Vol. II, prop. 70, pp. 296 –297), who
represents “God’s viceregent on earth”:

It is evidently for the public good that every member of
a state should submit to the governing power, whatever
that be. Peace, order, and harmony result from this in
the general [sic]; confusion and mischief of all kinds
from the contrary. (p. 296)
Hartley (1749/1971) held that good persons
do not challenge magistrates and they join mil-
itary service when commanded to do so. In turn,
a magistrate’s duty is to serve as a benevolent
“father of a people” (p. 305). Just as “private
persons . . . to obtain [their] greatest happiness
. . . must obey the precepts of benevolence,
piety, and the moral sense,” so should civil
authorities and even “foreign states” (p. 306).
Submission to civil authority also included
viewing “property as a thing absolutely deter-
mined by the laws” (Vol. II, prop. 70, p. 297).
His rationale was “Benevolence [is] the rule of
duty, public good the end of benevolence, and
submission to magistrates [civil authorities] is
the means of promoting the public good” (p.
297). However, Hartley’s interest in benevo-
lence was not balanced by economic justice.
On the one hand, Hartley (1749/1971) be-
lieved governments will be “overturned,” be-
cause they are innately corrupt and thus cannot
approximate his ideal society. For him, the
“body politic” is analogous to the “body natu-
ral” in tending toward “destruction and dissolu-
tion,” and it is romantic “to project the scheme
of a perfect government in this imperfect state
[of society]” (Vol. II, prop. 81, p. 369). On the
other hand, Hartley regarded civil and religious

government as intertwined. Thus, Christians
must “obey both the civil and ecclesiastical
powers under which they were born” (Vol. II,
prop. 82, p. 374), because they represent “God’s
viceregent on earth” (Vol. II, prop. 70, p. 296 –
297). They also are duty-bound to evangelize all
nations, he asserted. Clearly, Hartley’s views on
the self and society represent a conservative
political standpoint.
Hartley’s Synthesis and Subsequent
Psychological Thought
Hartley’s biophysical perspective, grounded
in natural philosophy, led him to reject the
dualism of an immaterial mind/soul against a
material body. For him, a material mind inte-
grates all physiological, psychological, and re-
ligious phenomena:
By presenting religious and moral ideas as determined
in the same manner and with the same necessity as
ideas of the physical world, Hartley made it possible to
argue that such ideas are as valid as our ideas of the
trees and rocks that we “see,” and that religious and
moral laws have an objective existence in “reality” as
well as a subjective existence in the mind. (Haven,
1959, p. 480)
Given that many contemporaries shared this
perspective, Hartley’s synthesis seemed empir-
ically legitimate and his influence extended to
continental Europe after German, French, and
Italian translations of Observations (Allen,
2013). The reformist physician Benjamin Rush

(1746 –1813) was one U.S. figure who was im-
pressed by Hartley’s integration of natural sci-
ence, metaphysics, and Christian beliefs and
was enthused about practical applications of his
ideas (C. Smith, 1987).
Yet in positing body–mind connectedness
mechanistically, Hartley (1749/1971) might
have employed a literalist interpretation of hy-
pothesized corporal vibrations and association
(Danziger, 2008). During his lifetime, of
course, neurophysiological knowledge was
rather limited and the tools needed to confirm
vibrations did not exist. In contrast, David
Hume (1711–1776) also posited that the asso-
ciation of ideas operates deterministically (C.
Smith, 1987). (He and Hartley likely were un-
aware of each other’s work; Allen, 2013). But
Hume saw the value of mechanics to rest in the
analogy of mental associations between sensory
impressions and ideas operating like Newton’s
corpuscular bodies that give coherence to the
physical world. Hume’s metaphorical interpre-
tation would provide a useful rationale for those
early psychologists who aimed to explain psy-
chological phenomena independently of physi-
ology (Danziger, 2008).
As to subsequent scholars, Reid, like Hartley,
believed that moral sensibility is the capacity
that enables knowing the right course of action
and exercising conscious monitoring of the ac-
tion itself (Lehrer, 1989). Reid’s views also
converged with Hartley’s regarding individuals
securing protection and socioeconomic benefits
by contributing to the well-being of society

(Haakonssen, 1990). However, although Reid
58 WALSH
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accepted Newtonian laws of nature, he held that
moral laws are not reducible to biophysical
ones. According to Reid’s conception of “com-
mon sense,” once beliefs held in common are
certain, we know what moral conduct is, on the
basis of empirical induction and introspection.
Thus, for him and contrary to Hartley, episte-
mology is foundational to morality, and moral
conduct is intertwined with both practical rea-
son and will.
Within Kant’s deontological system, by con-
trast, behaving morally entails confronting
one’s radical freedom to exercise the will to act.
For Kant, the mind organizes experience
(Brook, 1994), and the capacity for reason is the
fount from which ethical judgments should flow
(Leary, 1982). Self-awareness and the self as a
moral agent hold pride of place in his system.

Although he upheld the concept of individual
freedom of action, Kant argued that the state is
the means for actualizing freedom, including
property rights. Like Hartley, he stressed the
importance of a social contract to encompass
the common good so as to ensure everyone’s
well-being, including the destitute. As a loyal
subject of the Prussian monarchy, Kant advised
compliance with the state, opposed rebellion,
and supported capital punishment (Kneller,
2006).
Some practitioners of natural philosophy who
also were social reformers found Hartley’s
(1749/1971) ideas appealing. Joseph Priestley
(1733–1804), the renowned chemist, published
an abridged version of Hartley’s book in 1775,
from which Priestly excised the moral and reli-
gious content, to emphasize the scientific foun-
dations of social reform in the concept of asso-
ciation (Walls, 1982). For Priestley, Hartley’s
theory showed that societal conditions shape
conduct (R. Smith, 1997). However, he omitted
the concept of vibrations, which distorted Har-
tley’s system in that vibrations enable the pro-
gression of simple to complex to decomplex
associations.
Culturally, some Romantic poets took up
Hartley’s notion of theopathy as a turning into
spiritual reality (Richardson, 2001). For Samuel
Taylor Coleridge (1772–1834), Hartley’s syn-
thesis made “the religious experience of anni-
hilation of self and union with God” scientifi-
cally credible (Haven, 1959, p. 481). As well,
four psychological themes derived from Obser-

vations resonated in Romanticism: the close
relationship among animal and human sensory,
emotional, and mental properties, exemplified
by infants’ development of speech; the function
of sensory impressions as “miniatures” of com-
plex ideas, like the capacity of poets to experi-
ence vivid sensory impressions that arouse in-
tense emotions and complex ideas, independent
of the direct action of objects on a person; the
potential for internalized imagery to evoke
emotional aftereffects and for inner stress to
evoke emotionally painful dreams; and the
alignment of pain with pleasure and the body’s
capacity to assuage pain (Knox-Shaw, 2011).
In addition, 19th-century philosophical psy-
chologists James Mill (1773–1836), John Stuart
Mill (1806 –1873), and Alexander Bain (1818 –
1903), agreed with Hartley that association is
the basic process that produces all mental struc-
tures (Allen, 2013). The younger Mill credited
him with his own concept of “mental chemis-
try” (i.e., compounded associations that like a
chemical union are more than the sum of their
parts), but insisted that his father was Hartley’s
superior as a philosopher. For the Mills and
Bain, mental processes originated in the expe-
rience of associated thoughts, not in bodily pro-
cesses. Hartley (1749/1971) promoted the op-
posite view: “The powers of generating ideas
and raising them by association must also arise
from corporeal causes, and consequently admit
of an explication from the subtle influences of
the small parts of matter on each other” (Vol. I,
prop. 11, p. 72). In fact, 20th-century physiol-

ogists were to verify his notion that the brain is
the organ of thought (Richardson, 2001).
Hartley’s Synthesis and Modern Psychology
When natural-science psychology (i.e., the
study of psychological phenomena as natural
objects in terms of causal laws) ascended to
cultural prominence in the 20th century (Teo,
2005; Walsh et al., 2014), it overshadowed
earlier philosophical psychologists’ interest
in Hartley’s union of the biological, psycho-
logical, social, religious, and moral (Allen,
2013). Yet when behaviorists adopted the
concept of association, they limited it to ex-
planations of basic learning. Other parallels
between Hartley’s and modern psychologists’
concepts are apparent.
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Relation to Behaviorism

Originally in natural-science psychology, as-
sociation typically was viewed in terms of pas-
sive mental processes, leading to the conclusion
that Hartley’s (1749/1971) ideas were closer
than other natural philosophers to establishing
the intellectual framework for the new disci-
pline (Walls, 1982), at least in the United States.
Elsewhere when scientific psychology emerged
internationally, different conceptual emphases
were manifest (Walsh et al., 2014). But associ-
ationism, concretized as stimulus–response con-
nections and laws of contiguity and repetition,
undergirded behaviorism (Boring, 1950), which
B. F. Skinner’s (1904 –1990) operant condition-
ing model epitomized.
Yet associationism alone could not capture
Hartley’s (1749/1971) system of thought. Al-
though he regarded the formation of ideas
through association as equivalent to physical
processes involving natural elements, that was
simply the first stage of his synthesis. As Ob-
servations shows, Hartley also employed asso-
ciation to explain complex psychological pro-
cesses, interpersonal and social relations, union
with the divine, and moral conduct. Thus, asso-
ciation does not refer solely to a biologically
based phenomenon; rather, Hartley used it met-
aphorically to give meaning to the constellation
of psychological, social, religious, and moral
phenomena. Those psychologists who em-
ployed a literalist notion of association by-
passed this broader and deeper meaning. From
their perspective, the social, moral, and reli-
gious aspects of Hartley’s synthesis, which suf-
fuse Observations, likely appeared irrelevant, if

not antithetical to psychology. Skinner’s asso-
ciationist school of thought, for example, differs
radically from Hartley’s system, and Skinner’s
(1948, 1971) utopian societal treatises are res-
olutely secular.
Other Parallels in Psychology
From an international perspective on the his-
tory and philosophy of psychology (Walsh et
al., 2014), parallels between Hartley’s (1749/
1971) concepts and developments in modern
psychology are apparent. Theodule Ribot’s
(1839 –1916) and Hugo Münsterberg’s (1863–
1916) respective conceptual integrations of
thinking and action echo Hartley’s union of
thinking with voluntary and involuntary kinetic
activity. For all three theorists, association cat-
alyzes the relationship between perception and
action, which J. J. Gibson (1904 –1979) later
studied. In addition, Gestalt psychologists’ con-
cept of meaningful perception of phenomena
resembles Hartley’s holistic notion that individ-
uals derive meaning from a complete linguistic
expression that captures decomplex ideas. As
well, Lev Vygotsky (1896 –1934), like Hartley,
showed how language from its earliest stage is
fundamentally social and shapes human action.
Lastly, there appear to be parallels between the
motivational dimensions of Hartley’s synthesis
and diverse psychoanalysts’ stress on uncon-
scious dynamics occurring intrapersonally and
interpersonally.
Concerning biological psychology, Har-

tley’s (1749/1971) speculations about local-
ized brain functions and specific nerve
energies emerged as key hypotheses in 19th-
century physiology (Walls, 1982). In addi-
tion, Ivan Pavlov’s (1849 –1936) conclusions
about sensory nerves and later neurophysiolo-
gists’ interpretation of action potentials in
sensory nerves resemble Hartley’s concept of
sensory vibrations irradiating the brain (C.
Smith, 1987). After World War II, further
counterparts with Hartley’s notions material-
ized. Donald Hebb’s (1904 –1985) “cell-
assemblies” concept, in particular, is similar
to Hartley’s compounded associations. Ac-
cording to Hebb (1958), neurons group them-
selves into a neural-cell assembly by means
of sensory experience; this grouping “corre-
sponds to a particular sensory event or a com-
mon aspect of a number of sensory effects”
(p. 628). For Hebb, a given assembly corre-
sponds to a particular image or thought. Cell
assemblies prepare perceptual sensitivity for
particular stimuli, whereas interacting neu-
rons become associated permanently, which
is known as “Hebb’s rule.” Currently, Har-
tley’s notion of vibrations is paralleled by
action potentials traversing sensory nerves,
whereas “joint impression” is akin to a cog-
nitive-labeling process shaping perceptual
categories. Overall, neural capacities for per-
ceptual and cognitive categorization, con-
sciousness, memory, and language support
the view that association aids forming mental
structures (Walsh et al., 2014).
60 WALSH

in
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dl
y.
Historiographical and Philosophical
Reflection
From a “sophisticated-presentist” perspective
on history, which is the use of historical re-
sources to elucidate current perspectives theo-
retically (Walsh et al., 2014), it seems that, if
psychologists have been acquainted with Har-
tley’s (1749/1971) Observations, they likely
have had difficulty viewing his systematic state-
ment of 18th-century English psychology as
germane to the discipline. Informed by natural
philosophy, his synthesis encompassed a broad
spectrum of psychological processes for the
purpose of revivifying moral conduct in accord
with his religious yet materialist beliefs. At the
heart of his synthesis is the transit of sympathy,
theopathy, and moral sensibility as sequential
transformations of the self. As such, his system
might have been metaphorical anathema to
those who a priori rejected the value of religious
and spiritual beliefs and practices for psycho-

logical knowledge. After all, many early psy-
chologists expended much energy striving to
distinguish their new science from pseudoscien-
tific practices of the day (e.g., spiritualism) to
ensure the academic survival of the new science
(Coon, 1992).
As we have seen, however, Hartley (1749/
1971) neither relied on mechanistic and deter-
ministic explanations exclusively nor attributed
the development of compounded ideas to pas-
sive processes of association. In fact, instead of
serving as “the very model of a modern major
prophet of associationist psychology,” to para-
phrase the patter song from Gilbert and Sulli-
van’s operetta “The Pirates of Penzance,” he
understood association as a multipurpose and
complex concept that met an explicitly evangel-
ical aim. Hartley’s overarching vision was “the
pure happiness that comes from total identifica-
tion with God’s purposes” (R. Smith, 1997, pp.
252–253). His premise was that God inclines
humans toward moral conduct and happiness,
whereas his chief interest was how a person
“learns to love the good—and to act upon that
love” (Allen, 1999, p. 290). Moreover, he was
not unusual in addressing morality and religion,
inasmuch as many of his Enlightenment peers
did as well (Walsh et al., 2014). Consequently,
to perpetuate the historiographical tradition in
psychology of limiting Hartley’s notion of as-
sociation to sensory-motor and learning pro-
cesses, while footnoting or ignoring his concep-
tions of social relations, relationship with a
divine being, and moral sensibility, not only

misrepresents his approach but constitutes a
missed opportunity for contemporary psycholo-
gists to explore these issues.
Hartley’s (1749/1971) synthesis, I would ar-
gue, serves as an analogy to potential concep-
tions of psychological theory and practice that
transcend the philosophical prejudices of past
psychology against incorporating religious and
spiritual experience in the discipline (see James,
1902; Spilka, 1987). From a human-science
perspective on psychology that aims to under-
stand and interpret the meaning of human action
in social historical context (Teo, 2005), Har-
tley’s stress on transcending the ego to effect
both self-actualization and union with the di-
vine is akin to concepts in transpersonal psy-
chology (Maslow, 1969), which is focused on
spiritual and religious experience (e.g., Wal-
lace, 2012). Such a focus is scientifically rea-
sonable for the discipline, given that many peo-
ple consider themselves religious, spiritual, or
both (Bergin, 1991; Leeming, 2014; Richards,
2011). Furthermore, aboriginal peoples in North
America view a right relation with “the creator”
as integral to their personal and collective iden-
tity, endeavoring to live in harmony with the
created world, participate in religious ceremo-
nies and spiritual practices, and behave morally
to ensure the common good (Mohawk, 2010).
Accordingly, it makes empirical sense for psy-
chology to expand its horizons by engaging
with culturally diverse points of view on reli-
gion and spirituality (e.g., Walsh-Bowers,
2000).

At the least, familiarity with Hartley’s (1749/
1971) complex description of human nature,
featuring the developmental manifestations of
sympathy, theopathy, and moral sensibility,
might encourage more psychologists to incor-
porate religious, spiritual, and moral aspects of
the human condition in the discipline’s theory,
practice, and curricula than has occurred thus
far. Ideally, by broadening and deepening the
discipline’s domain of interests, scientific psy-
chology would do greater justice than it has in
the past to the complex realities of the human
condition that religious and spiritual beliefs and
practices and moral sensibility reflect. The re-
sult might be enhanced human validity for our
inquiries and interventions with individuals,
T
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families, groups, and communities, with whom
we share a common humanity. Moreover, the
ramifications of climate change for the sustain-
ability of human life on Earth suggest the ur-

gency for a social-ethical reorientation in psy-
chology, grounded in a revolutionary praxis of
environmental, economic, and social justice,
and compassion (Walsh & Gokani, 2014;
Walsh, 2015). For some psychologists and other
citizens, religious and spiritual beliefs and prac-
tices would inspire such a reorientation,
whereas for others secular morality would suf-
fice.
However, certain impediments to psycholo-
gists incorporating the study of religious and
spiritual experience must be acknowledged.
Historically the institutionalization of a natural-
science orientation in psychology has marginal-
ized the value of a human-science orientation
that poses research questions typically requiring
qualitative methods to answer them (Walsh et
al., 2014). Yet from the era of functionalism to
current cognitive neuroscience, an ideology of
materialistic and mechanistic reductionism has
prevailed in the discipline’s theory, research,
professional practice, and education, which mil-
itates against qualitative study of religious and
spiritual experience. The critical concept of sci-
entism (Habermas, 1968/1972) captures this in-
tellectual tradition, expressed partly in virtually
fundamentalist adherence to objectivistic meth-
odological beliefs and practices (Walsh-
Bowers, 1999). A scientistic disposition is par-
ticularly ironic—and disappointing—when
juxtaposed against psychologists’ reluctance to
accommodate religious and spiritual experi-
ence. Therefore, until the discipline fosters a
facilitative intellectual and social climate of
catholicity by encouraging philosophical, theo-

retical, and methodological pluralism (Walsh-
Bowers, 2010) and by providing the appropriate
institutional resources that can enable col-
leagues and students to pursue the theories and
methods that match their research questions, the
marginalization of religious and spiritual expe-
rience likely will endure in psychology.
References
Allen, R. C. (1999). David Hartley on human nature.
Albany, NY: SUNY Press.
Allen, R. (2013). David Hartley. In E. N. Zalta (Ed.),
The Stanford encyclopedia of philosophy. Re-
trieved from http://plato.stanford.edu/archives/
sum2013/entries/hartley/
Bergin, A. E. (1991). Values and religious issues in
psychotherapy and mental health. American Psy-
chologist, 46, 394 – 403. http://dx.doi.org/10.1037/
0003-066X.46.4.394
Billig, M. (2008). The hidden roots of critical psy-
chology. London, England: Sage.
Boring, E. G. (1950). A history of experimental psy-
chology (2nd ed.). New York, NY: Appleton-
Century-Crofts.
Brook, A. (1994). Kant and the mind. New York,
NY: Cambridge University Press. http://dx.doi
.org/10.1017/CBO9780511624629
Coon, D. J. (1992). Testing the limits of sense and

science: American experimental psychologists
combat spiritualism, 1880 –1920. American Psy-
chologist, 47, 143–151. http://dx.doi.org/10.1037/
0003-066X.47.2.143
Danziger, K. (2008). Marking the mind: A history of
memory. New York, NY: Cambridge University
Press. http://dx.doi.org/10.1017/CBO9780511
810626
Darwall, S. (2005). Berkeley’s moral and political
philosophy. In K. P. Winkler (Ed.), The Cam-
bridge companion to Berkeley (pp. 311–338). New
York, NY: Cambridge University Press. http://dx
.doi.org/10.1017/CCOL0521450330.011
Fairchild, H. N. (1942). Religious trends in English
poetry: Vol. II. 1740 –1780: Religious sentimental-
ism in the age of Johnson. New York, NY: Co-
lumbia University Press.
Gay, P. (1968). Deism: An anthology. New York,
NY: Van Nostrand.
Haakonssen, K. (1990). Introduction. In K. Haakon-
ssen (Ed.), Thomas Reid: Practical ethics (pp xi–
lxxxvii). Princeton, NJ: Princeton University
Press.
Habermas, J. (1972). Knowledge and human interest
(J. J. Shapiro, Trans.). Boston, MA: Beacon Press.
(German original published in 1968)
Hartley, D. (1971). Observations on man, his frame,
his duty, and his expectations (Vols. I & II). New
York, NY: Garland. (Original work published

1749)
Haven, R. (1959). Coleridge, Hartley, and the mys-
tics. Journal of the History of Ideas, 20, 477– 494.
http://dx.doi.org/10.2307/2707887
Hebb, D. O. (1958). Biological and biochemical
bases of behavior (2nd ed.). Madison, WI: Univer-
sity of Wisconsin Press.
Hirst, J. (2005). Jane Leade: Biography of a seven-
teenth-century mystic. Aldershot, England: Ash-
gate.
James, W. (1902). The varieties of religious experi-
ence: A study in human nature. New York, NY:
Longmans, Green. http://dx.doi.org/10.1037/
10004-000
62 WALSH
T
hi
s
do
cu
m
en
t
is
co

du
al
us
er
an
d
is
no
t
to
be
di
ss
em
in
at
ed
br
oa
dl
y.
Kelly, P. (2005). Berkeley’s economic writings. In
K. P. Winkler (Ed.), The Cambridge companion to

Berkeley (pp. 339 –368). New York, NY: Cam-
bridge University Press. http://dx.doi.org/10.1017/
CCOL0521450330.012
Kneller, K. (2006). Kant on sex and marriage right.
In P. Guyer (Ed.), The Cambridge companion to
Kant and modern philosophy (pp. 447– 476). New
York, NY: Cambridge University Press. http://dx
.doi.org/10.1017/CCOL052182303X.014
Knox-Shaw, P. (2011). Coleridge, Hartley, and “The
Nightingale.” The Review of English Studies, 62,
433– 440. http://dx.doi.org/10.1093/res/hgq123
Leary, D. E. (1977). Berkeley’s social theory: Con-
text and development. Journal of the History of
Ideas, 38, 635– 649. http://dx.doi.org/10.2307/
2708692
Leary, D. E. (1982). Immanuel Kant and the devel-
opment of modern psychology. In W. R. Wood-
ward & M. G. Ash (Eds.), The problematic sci-
ence: Psychology on nineteenth-century thought
(pp. 17– 42). New York, NY: Praeger.
Leeming, D. A. (Ed.). (2014). Encyclopedia of psy-
chology and religion (2nd ed.). New York, NY:
Springer.
Lehrer, K. (1989). Thomas Reid. London, England:
Routledge.
Locke, J. (1975). In P. H. Nidditch (Ed.), An essay
concerning human understanding. Oxford, Eng-
land: Clarendon. (Original work published 1690)

Maslow, A. (1969). The farther reaches of human
nature. Journal of Transpersonal Psychology, 1,
1–9.
Mohawk, J. (2010). In J. Barreiro (Ed.), Thinking in
Indian: A John Mohawk reader. Boulder, CO:
Fulcrum.
Richards, G. (2011). Psychology, religion, and the
nature of the soul. New York, NY: Springer. http://
dx.doi.org/10.1007/978-1-4419-7173-9
Richardson, A. (2001). British Romanticism and the
science of the mind. New York, NY: Cambridge
University Press. http://dx.doi.org/10.1017/
CBO9780511484469
Robinson, D. N. (1995). An intellectual history of
psychology (3rd ed.). Madison, WI: University of
Wisconsin Press.
Royce, J. E. (1961). Man and his nature. New York,
NY: McGraw-Hill.
Skinner, B. F. (1948). Walden Two. New York, NY:
Macmillan.
Skinner, B. F. (1971). Beyond freedom and dignity.
New York, NY: Knopf.
Smith, C. U. M. (1987). David Hartley’s Newtonian
neuropsychology. Journal of the History of the
Behavioral Sciences, 23, 123–136. http://dx.doi
.org/10.1002/1520-6696(198704)23:2�123::AID-
JHBS2300230203�3.0.CO;2-D

Smith, R. (1997). The Norton history of the human
sciences. New York, NY: Norton.
Spilka, B. (1987). Religion and science in early
American psychology. Journal of Psychology and
Theology, 15, 3–9.
Swartz, N. (1985). The concept of physical law. New
York, NY: Cambridge University Press.
Teo, T. (2005). The critique of psychology: From
Kant to post-colonial theory. New York, NY:
Springer.
Wallace, B. A. (2012). Meditations of a Buddhist
skeptic: A manifesto for the mind sciences and
contemplative practice. New York, NY: Columbia
University Press.
Walls, J. (1982). The psychology of David Hartley
and the root metaphor of mechanism: A study in
the history of psychology. Journal of Mind and
Behavior, 3, 259 –274.
Walsh, R. T. G. (2015). Bending the arc of North
American psychologists’ moral universe toward
communicative ethics and social justice. Journal
of Theoretical and Philosophical Psychology, 35,
90 –102. http://dx.doi.org/10.1037/teo0000011
Walsh, R. T. G., & Gokani, R. (2014). The personal
and political economy of psychologists’ desires for
social justice. Journal of Theoretical and Philo-
sophical Psychology, 34, 41–55. http://dx.doi.org/
10.1037/a0033081

Walsh, R. T. G., Teo, T., & Baydala, A. (2014). A
critical history and philosophy of psychology: Di-
versity of context, thought, and practice. New
York, NY: Cambridge University Press.
Walsh-Bowers, R. (1999). Fundamentalism in psy-
chological science: The Publication Manual as Bi-
ble. Psychology of Women Quarterly, 23, 375–
392. http://dx.doi.org/10.1111/j.1471-6402.1999
.tb00368.x
Walsh-Bowers, R. (2000). A personal sojourn to spir-
itualize community psychology. Journal of Com-
munity Psychology, 28, 221–236. http://dx.doi.org/
10.1002/(SICI)1520-6629(200003)28:2�221::
AID-JCOP8�3.0.CO;2-S
Walsh-Bowers, R. (2010). Some social-historical is-
sues underlying psychology’s fragmentation. New
Ideas in Psychology, 28, 244 –252. http://dx.doi
.org/10.1016/j.newideapsych.2009.09.018
Webb, M. E. (1988). A new history of Hartley’s
Observations on Man. Journal of the History of the
Behavioral Sciences, 24, 202–211. http://dx.doi
.org/10.1002/1520-6696(198804)24:2�202::AID-
JHBS2300240207�3.0.CO;2-X
Westfall, R. (1980). Never at rest. New York, NY:
Cambridge University Press.
Received January 25, 2016
Revision received April 27, 2016
Accepted July 24, 2016 �

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