A Swiss Biologist.
First Profound interest in epistemology.
Later developed interest in child & cognitive psychology.
In 1920, associated with the Binet Testing Laboratory in
Opposed Binet’s idea of defining intelligence in term of the
number of correct responses .
Defined intelligence as the ability to adjust ,adopt or
deal efficiently with one’s environment.
He & his wife devoted his early married life to study
the intellectual development of their own three
His theory of intellectual development has no parallel
in the history.
Unlike other creatures , the human baby is born with a
few practical instincts and reflexes such as sucking
,looking, reaching and grasping.
The initial cognitive structure of infants is supposed
to incorporate only those cognitive abilities which help
them to do such acts such as suck, look and grasp.
Piaget named these abilities or potential as “schemas”
A schema represents a unit of one's cognitive structure
in the shape of general potential to perform a
particular class of behaviors (like sucking, grasping,
For example take sucking schema, it refers to one’s
general cognitive ability to suck objects. It can be
thought of as a cognitive structure that makes all acts
of sucking possible. But specific responses to specific
The various schemas form the basic structure of the
The structure of an organism is said to play a decisive
role in its functioning.
Therefore , what is available to an individual in term of
his schemas decides how is he going to respond to the
stimuli present in his physical and social environment.
On the other hand , the individual has to adopt to his
environment for survival as well as proper growth and
The task of such adaptation is carried out through the
process of assimilation and accommodation.
Assimilation refers to a kind of matching between the
already existing cognitive structure and the
environmental needs as they arise.
In a situation where a six – month old infant is given a
new toy it is likely to respond by putting the toy in its
mouth. This is assimilation.
Q; Why does he do so?
In case the new toy is too big to be picked up and
placed in mouth , it will certainly need a change or
modification in the already existing cognitive
Now the child will have to change his old way of
thinking and behaving in order to adopt or adjust to
the new situation .
Consequently , now instead of sucking, the child may
respond by pushing or grasping the toy. This is called
The process of assimilation and accommodation helps
the organism to adjust or maintain a harmonious
relationship between himself and his environment.
This adjustment mechanism was called equilibration
1. The Biological inherited reflexes.
2. The change & development brought about in the
cognitive structure.(The process of Natural Growth)
3. The change & development in the cognitive structure
brought about through experiences.
The Sensory-motor Stage (from birth to 2 years)
Piaget called the first stage of intellectual development the
sensory-motor stage. Because:
a. It is characterized by the absence of language.
b. As the name implies, the infant uses senses and motor abilities
to understand the world.
c. It is limited to direct sensory interactions with the
In this stage , the cognitive development occurs along the
1. At birth the infant exhibits a limited number of
uncoordinated reflexes such as sucking , looking ,
reaching and grasping.
2. During next four month the uncoordinated reflexes are
coordinated into simple schemas e.g. the infant now
tries to suck anything which is put into his mouth
stares at whatever he sees ,
reaches for everything and grasps all that put into his
(3) First his view about environmental objects is that what is out of
sight is purely out of mind.
Gradually the concept of object permanence evolves in the cognitive
structure of the infant.
By the age of 8 months the infant is able to react to objects outside
He begins to realize that object around are separate from himself and
they have their independent and permanent existence.
While stepping into this stage , the child begins to
replace direct action in the form of sensory or motor
exploration with symbols.
The learning of language provides him with a good
tool for thinking. He begins to utter words to ask for
something rather than just reaching out to get it.
This stage can be further sub divided into
1. The Pre-Conceptual phase (2 to 4 years)
2. Intuitive phase (4 to 7 years)
a) In this early part, the children seem to identify object
by their names but make mistakes in this process of
identification and concept formation e.g. they think
all men are daddy & all women are mummy.
b) Their mode of thinking and reasoning is quite
illogical at this stage. (e.g. cow)
c) Their thinking is sometime too imaginative and they
cannot distinguish between living and non living.
(e.g. block of wood , doll)
d) They have egocentric nature. Child thinks the world
is only for him.
At this stage
a) Various concepts of child are at more advanced level.
b) But what he thinks or solves is carried out intuitively,
rather than logically.
c) His thinking are full of contradictions.
d) Absence of two main cognitive characteristics
(1) Reversibility (2) conservation
In this stage
a) Now he learns to deal with concepts and ideas that
only in mental terms.
b) Thinking becomes more logical and systematic.
c) Develops the ability to conserve both in terms of
quantity and number of objects.
d) Develops the ability to reverse.
e) No longer ego-centric in his thinking.
At this stage
a) The intellectual development and functioning takes a very
b) Learns to deal with abstraction by logical thinking.
c) Believes that hypothetical problem can also be solved mentally as
d) Creative aspects are much visible.
e) High level of intellectual functioning developed
In short , according to Piaget ,this stage is usually
characterized by the presence of the most
sophisticated cognitive abilities to
(a) build up multiple hypotheses & a number of
(b) verify all possible solutions in a systematic &
(c) generalize & arrive at abstract that covers many