Judge Posner defines the jurisprudence of skepticism and explores its main forms and implications for legal theory and practice. He argues that many legal problems cannot be solved through traditional legal reasoning alone and require importing perspectives from other domains. This gives rise to an "epistemological skepticism" about law's determinacy. Posner also examines different forms of legal reasoning like formalism and their limitations. Ultimately, he concludes that neither pure nor practical reason can provide law with certainty. This means judges must adopt a modest, moderate approach grounded in pragmatism when resolving complex cases with indeterminate outcomes.

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LEGAL THEORY
ON SKEPTICISM
Richard A. Posner (1988). ‘The Jurisprudence of Skepticism,’ Michigan Law Review,
Vol. 86, pp. 827-891.
INTRODUCTION
What does Judge Posner mean by the jurisprudence of skepticism?
This essay will summarize the main points raised by Judge Richard Posner of the
U.S. Court of Appeals, Seventh Circuit, and the University of Chicago’s School of
Law. Judge Posner identifies the skeptical vein in a number of thinkers like Plato,
Hobbes, Bentham, Oliver Wendell Holmes, and in the traditions of legal realism and
critical legal studies. The purpose of his paper is to explain what this tradition stands
for in legal thought, situate his own judicial credo, and ‘defend a moderately
sceptical approach to law and judging.’ Judge Poser starts by noting that many legal
problems cannot be addressed by invoking the usual models of legal reasoning. The answers
to these problems are imported from the policy arena or the legal philosophy of
judges who have to solve these problems. Since solutions do not emerge naturally
within the forms of reasoning internal to the law, and the problems are
indeterminate by definition, it gives rise to a form of ‘epistemological scepticism.’
There is also another form of scepticism that Judge Posner terms ‘ontological
scepticism.’ The latter relates to abstract entities that the judiciary deploys in the
context of adjudication like ‘justice’ and ‘legislative intent.’ The question is whether
these entities really exist; and, if they don’t, what implications that will have for the
existence of the mind and the mental entities that are invoked in criminal law, the
law of torts, and so on. What interests Judge Posner is not global scepticism where

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everything is subject to systematic doubt, but a more ‘local form of scepticism.’ The
reason for this is that local scepticism characterizes Justice Holmes’ approach to
jurisprudence; it is therefore worth studying closely. Judge Posner’s preoccupation
with skepticism is related to the fact that it can be stimulative for thinking about how
judges think. Skepticism is more of an ‘attitude’ rather than reducible to asking
whether the jurist is a realist or a nominalist in terms of legal doctrine. Not all forms
of skepticism are the same since there are also ‘degrees of skepticism’ to contend
with. Judge Posner describes himself as ‘moderate’ in his skepticism and in his
judicial approach. Skepticism can take the former of doubting whether a determinate
approach is at all feasible in the law. Or, it can take the form of questioning whether
legal reasoning is really what it is thought to be.
FORMS OF LEGAL REASONING
In order to pave the way for a skeptical approach, Judge Posner considers how
human being acquire beliefs and differentiates between ‘pure reason’ and ‘practical
reason’ in the context of the forms of legal reasoning. Judge Posner starts his query
into legal reasoning by pointing out that the legal profession would like to believe
that legal reasoning is reducible to the logical syllogism. In this approach, the major
premise is the applicable rule in law, the minor premise constitutes the facts of the
case, and the conclusion is the resolution actually arrived at in the case. The rule
itself is extracted from the previously existing law or from the legal materials in a
given case. This approach is known as legal formalism. This approach is viable in a
large number of cases as long as the legal rule is considered to be valid. In that sense,
it gives the impression that the law – considered as a rule or as a collection of rules -
is determinate, objective, and even predictable. But there are clear limits to this
approach. If that is not understood, then, we will wind up in a situation where jurists
invoke the form of a syllogism even if the legal problem is not subject to a syllogistic
analysis from a substantive point of view. Likewise, when jurists use the notion of
‘equality’ in legal reasoning, it is not the same as establishing a formal equivalence in
syllogistic logic. Equality in the law is more likely to be a political term than a logical
term. As Judge Posner puts it, ‘it is a statement of policy rather than a method for

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avoiding contradictions.’ Furthermore, unlike the structure of a logical syllogism, in
legal reasoning there are a number of minor premises that have to be invoked to
accommodate case facts. The major premise will also depend on a legal definition
which must be agreeable to both parties. That is why it is much more difficult to
deploy syllogistic forms of reasoning in complex cases.
LOGIC & EXPERIENCE
In practice, we find that there are a number of ‘exceptions’ to this form of legal
reasoning because judges have the discretion to admit exceptions during litigation. Judges
will also have to interpret rules; the interpretation of rules is not neatly reducible to
logic. A logical inference is true only if the premises are true; often in the law it is not
clear if the premises themselves are true. That is why Justice Holmes argued that ‘the
history of the law has not been logic but experience.’ There is a difference then
between saying that logic has a part to play in legal reasoning and saying that legal
reasoning is reducible to logic as such. If even mathematics is not reducible to logic,
how can the law be reduced to logic? If the law is not as logical as we would like it to
be, can we at least envisage a scientific model for the law? Is there, for instance, such
a thing as ‘the science of the law?’
Judge Posner points out that science itself is not as scientific as we think science
should be if by science what we have in mind is akin to ‘experimental science.’ There
are any number of scientific phenomena in areas like astronomy that are not
responsive to experiments. Euclidean geometry was for long considered to be
representative of the world, but that turned out to be wrong. In other words, as a
pragmatist, Judge Posner believes that all scientific theories are subject to revision.

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He invokes Karl Popper’s argument that a scientific theory can only be falsified; it
cannot be proved to be true because the next generation of scientists can come up
with a better theory. So the law does not measure up to either science or even to
forms of social engineering. The law, in other words, cannot be described through
the forms of ‘exact inquiry’ that characterize logic, science, and mathematics. It is
therefore better to check if practical reason can make more sense of it workings and
forms of reasoning.
ON PRACTICAL REASON
What is practical reason? Judge Posner defines practical reason as a collection of
methods involving both ‘investigation and persuasion.’ It involves elements like
common sense, imagination, induction, intuition, figuration, and experience which
involve the ability to infer larger patterns of social behaviour. The important thing to
note is that neither pure reason nor practical reason will yield ‘certainty’ as the basis
for judicial action. What practical reason can generate however is confidence. The
techniques used under the aegis of practical reason include the invocation of
‘authority, analogy, interpretation, means-ends rationality, tacit knowledge, and
temporality.’ Judge Posner then explains what these practical approaches mean in
theory and practice within the contexts of legal reasoning. His purpose in doing so is
to demonstrate the ‘limits of reason in adjudication,’ and why the law is not a science
or a form of ‘exact inquiry.’ In this, he is basically annotating Justice Holmes’
approach to the forms of legal reasoning in the common law. The inordinate length
of this paper is due to the inclusion of any number of expository sections to explain
what each particular form of practical reasoning is along with an analysis of its
strengths and weaknesses. But the purpose of the over-all argument is to make a
case for the Holmesian dictum that ‘certitude is not certainty.’
POSNER’S JUDICIAL CREDO
A skeptical philosopher – especially of the pragmatist type – is basically haunted by
this problem both in the context of pure and practical reason. Judge Posner’s point is
not that jurists should not read philosophy, but rather that they should moderate
their expectations since certainty in the law is not to be found neither in the pursuit

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of pure reason nor in the pursuit of practical reason. This necessarily means that the
jurist should adopt a judicial stance of modesty and moderation; that is exactly what
Judge Posner sets out to do in terms of his judicial credo. Judge Posner’s critique of
many forms of positive legal theory is that it is based on the assumption that each of
the theorists has found a model of certainty and the epistemological foundations that
would guarantee its validity. The practical implications then of this argument
amount to asking: What does it mean to decide cases in the absence of certainty?
How should we reason in the law when neither pure nor practical reason can
increase our levels of certainty? That is why the legal system has so much difficulty
in generating consensus, and it is difficult to pursue the ‘right answers’ to legal
quandaries. A number of controversial issues and cases still remain outside the
ambit of legal reasoning. The ‘skeptical judge’ is merely a jurist who has encountered
this situation in both the theory and the practice of law. It is therefore important – in
the absence of certainty – to be ‘reasonable’ in the context of the legal materials that
are actually available in any given case. If the legal materials lean in a particular
direction, it is easy for the judge to decide; if not, he will find himself in the ’open
area’ confronted with ‘the indeterminacy problem.’ In such a situation, Judge Posner
argues that there is no form of legal reasoning internal to the law itself that will be of
use. The judge must seek recourse then to some form of political theory or policy
analysis in order to resolve the case.
ON SKEPTICISM
In addition to epistemological skepticism, Judge Posner is also preoccupied with
ontological skepticism. This basically takes the form of a critique of mentalism and
the terms that relate to it in different branches of the law. Judge Posner explains that
the economic approach to the law allows comparisons between entities like ‘intent’
in torts and the ‘utility function’ in economics. That makes it possible to reduce mental
entities to observable parameters that can be measured. The mentalist approach then will
give way to the behavioural approach. It makes more sense to talk in terms of actual
‘conduct’ rather than in terms of abstruse ‘intent.’ Justice Holmes made precisely this
move in his analysis of criminal liability in his studies on the common law. What is

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really important then is to be able to predict what the subject will do rather than
analyse criminal intent in the calculation of liability. That is as true for intentional
tort as for liability in criminal law. While mentalist forms of reasoning cannot be
wished away completely, the economic approach to law is conscious of the need to
work with a minimalist ontology. The economic definition of ‘rationality’ then is not
related to mental states; it is ‘rather the state in which means are well fitted to ends.’
In other words, what Judge Posner is pushing for is a behaviourist approach to the
law rather than seek recourse to ‘mentalist explanations.’ That is because skeptics
want to invoke as few mental entities as possible or redefine them as stated above.
That is why attempts to define the law should avoid making an ontological entity of
the law itself and re-constitute it simply as the ‘activity of judges.’
CONCLUSION
In any case, attempts to define the law in the traditional sense will yield a ‘political
statement’ rather reveal what the law really is. Or, it will wind up making a
metaphysical entity of it like in the case of ‘natural law.’ So, Judge Posner concludes
that there is something ‘indefinable’ about the law; it cannot be exhausted by any
specific approach in legal theory. That is why Judge Posner is in favour of the
‘prediction theory’ of law (which has behaviourist dimensions) rather than an
ontological approach to the law which will dwell endlessly on what the law is. In
this approach based on prediction, all legal materials including precedents only
constitute the input factors and should not be conflated with the law as such. Judge
Posner points out that what Justice Holmes tried to do in invoking a genealogy for
the common law was to demonstrate that terms in the common law had a specific
origin in a ‘particular constellation of social circumstances.’ They are not absolute
legal entities that have always existed. That is the case with precedents as well.
When they are traced back to their point of origin, the jurist finds that they begin
with but a mere ‘assertion’ in a specific case before they are cited repeatedly within a
specific line of cases. But those who do not take the trouble to trace precedents back
to their origins will feel that precedents constitute the formal essence of the law in
any given matter. While Judge Posner doesn’t believe legal conventionalism is the

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‘antidote to formalism,’ he finds some similarities between the approaches of
pragmatism and conventionalism given that conventionalists are also haunted by the
forms of skepticism and the limitations of reason that bother pragmatists.
Though conventionalists invoke formalist rhetoric, Judge Posner finds that they do
so without subscribing to formalist assumptions in its entirety. The main advantage
of skepticism is that it helps us to identify pseudo-questions in the law. So, for
instance, what are legal theorists to make of the legal system in Nazi Germany? If the
law is understood as an activity, then it is not necessary to ask pseudo-questions
about racial laws in Nazi Germany. The significance of the Nuremburg trials then
was not to assure Nazis of the provisions of due process or render justice in some
absolute sense to the fallen enemy by the Allies, but to ensure that their ‘moral guilt
was established more convincingly than if they had been liquidated hugger-
mugger.’
SHIVA KUMAR SRINIVASAN