Reason

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This article is about the human faculty of reason or
rationality. For other related topics, see Reason
(disambiguation).

The
Sleep of Reason Produces Monsters (etching by Goya, c.
1799)

Reason is a mental faculty (or
ability) found in humans, that is able to generate conclusions from assumptions
or premises. In
other words, it is amongst other things the means by which rational beings propose
specific reasons, or explanations of cause and effect. In contrast to
reason as an abstract noun, a reason is a
consideration which explains or justifies.[1]

Reason is particularly associated with human nature, that which is
unique and definitive about being human. As a way of
coming to conclusions, it is often contrasted not only with the ways in which
non-human animals appear to make
decisions, but also with decisions based upon authority, intuition, emotion, mysticism, superstition, and faith. Reason is
thought by rationalists to be more
reliable in discovering what is true or what is best. The
precise way in which reason differs from emotion, faith, and tradition is controversial,
because all three are considered to be both potentially rational, and
potentially in conflict with reason.

The essential difference between reason and other modes of consciousness is in explanation: thinking is
more reasoned or rational if it is more consciously thought through in a way
which can be expressed in language.

Psychologists and cognitive scientists
study how people
reason, which cognitive and neural processes are engaged, how cultural
factors affect the inferences people draw. The properties of logic which may be used to reason
are studied in mathematical logic.
The field of automated reasoning
studies how reasoning may be modelled computationally.

Contents

1 Etymology

2 Reason compared to logic,
cause-and-effect thinking, and symbolic thinking

3 Logical reasoning methods
and argumentation

3.1 Deductive
reasoning

3.2 Inductive
reasoning

3.3 Abductive
reasoning

3.4 Analogical
reasoning

3.5 Fallacious
reasoning

3.5.1 Formal
fallacies

3.5.2 Informal
fallacies

4 Reason, truth, and "first
principles"

4.1 Justifying reason
itself

5 Reason, imagination,
mimesis, and memory

6 Reason and emotion or
passion

7 Reason in political
philosophy and ethics

8 Reason and faith

9 Psychology

9.1 Behavioral experiments
on human reasoning

9.2 Developmental studies
of children's reasoning

9.3 Neuroscience of
reasoning

10 Automated
reasoning

11 Meta-reasoning

12 See also

13 Further reading

14 References

15 Footnotes

[edit]
Etymology

The meaning of the word "reason" in senses such as "human reason" overlaps to
a large extent with "rationality" and the
adjective of "reason" in philosophical contexts is normally "rational", rather than
"reasoned" or "reasonable". The concept of "reason" is closely
related to the concepts of language and logic, as reflected in the
multiple meanings of the Greek "λόγος" logos, the root of logic, as per -logy, which
translated into Latin became ratio
(including mathematical ratio) and then in French raison,
from which the English word "reason" was derived.

[edit]
Reason compared to logic, cause-and-effect thinking, and
symbolic thinking

Main articles: Logic, Causality, and Symbols

The terms "logic" or "logical" are sometimes used as if they were identical
with the term "reason" or with the concept of being "rational", or sometimes
logic is seen as the most pure or the defining form of reason.

Reason and logic can however be thought of as distinct, although logic is one
important aspect of reason. Reason is a type of thought, and the word "logic" involves the
attempt to describe rules by which reasoning operates, so that orderly reasoning
can be taught. The oldest surviving writing to explicitly consider the rules by
which reason operates are the works of the Greek philosopher Aristotle,
especially Prior Analysis and Posterior Analysis.[2]
Although the Ancient Greeks had no separate word for logic as distinct from
language and reason, Aristotle's newly coined word "syllogism"
(syllogismos) identified logic clearly for the first time as a distinct
field of study. When Aristotle referred to "the logical" (hē logikē), he
was referring more broadly to rational thought.[3]

Author Douglas Hofstadter,
in Gödel, Escher,
Bach, characterizes the distinction in this way. Logic is done inside a
system while reason is done outside the system by such methods as skipping
steps, working backward, drawing diagrams, looking at examples, or seeing what
happens if you change the rules of the system.[4]

Another way to consider the confusion between logic and reason is that
computers and animals sometimes perform actions which are apparently logical:
from a complex set of data, conclusions are achieved which are "logical". Being
a cause of something which humans find logical does not necessarily mean that
computers or animals have reason, or even logic in the strict sense. Some
animals are also clearly capable of a type of "associative
thinking"—even to the extent of associating causes and effects.[5]
A dog once kicked, can learn how to recognize the warning signs and avoid being
kicked in the future.

Human reason is more than logic, requiring not just the possibility of
associating perceptions of smoke, for example, with memories of fire, but also
the ability to create and manipulate a system of symbols, as well as indices
and icons, according to Charles Sanders
Peirce, the symbols having only a nominal, though habitual,
connection to either smoke or fire.[6]

The connection of reason to symbolic thinking has been expressed in different
ways by philosophers. Thomas Hobbes described
the creation of "Markes, or Notes of remembrance" (Leviathan Ch.4) as
"speech" (allowing by his definition that it is not necessarily a means of
communication or speech in the normal sense; he was clearly using "speech" as an
English version of logos in this description[7]).
In the context of a language, these marks or notes are called "Signes" by
Hobbes.

[edit]
Logical
reasoning methods and argumentation

Looking at logical categorizations of different types of reasoning the
traditional main division made in philosophy is between deductive reasoning
and inductive reasoning.
Formal logic has
been described as "the science of deduction".[8]
The study of inductive reasoning is generally carried out within the field known
as informal logic or critical thinking.

[edit]
Deductive reasoning

Main article: Deductive
reasoning

Reasoning in an argument is valid if the argument's conclusion
must be true when the premises (the reasons given to support that conclusion)
are true. One classic example of deductive reasoning is that found in syllogisms
like the following:

Premise 1: All humans are mortal.

Premise 2: Socrates is a human.

Conclusion: Socrates is mortal.

The reasoning in this argument is valid, because there is no way in which the
premises, 1 and 2, could be true and the conclusion, 3, be false.

Validity is a property of the reasoning in the argument, not a property of
the premises in the argument or the argument as a whole. In fact, the truth or
falsity of the premises and the conclusion is irrelevant to the validity of the
reasoning in the argument. The following argument, with a false
premise and a false conclusion, is also valid (it has the form
of reasoning known as modus ponens).

Premise 1: If green is a color, then grass poisons cows.

Premise 2: Green is a color.

Conclusion: Grass poisons cows.

Again, if the premises in this argument were true, the reasoning is such that
the conclusion would also have to be true.

In a deductive argument with valid reasoning the conclusion contains no more
information than is contained in the premises. Therefore, deductive reasoning
does not increase one's knowledge base, and so is said to be non-ampliative.

Within the field of formal logic, a variety of
different forms of deductive reasoning have been developed. These involve
abstract reasoning using symbols, logical operators and
a set of rules that specify what processes may be followed to arrive at a
conclusion. These forms of reasoning include Aristotelian logic,
also known as syllogistic logic, propositional logic,
predicate logic, and modal
logic.

[edit]
Inductive reasoning

Main article: Inductive
reasoning

Induction is a form of inference producing propositions about unobserved
objects or types, either specifically or generally, based on previous
observation. It is used to ascribe properties or
relations to objects or types based on previous observations or
experiences, or to formulate general statements or laws based on limited
observations of recurring phenomenal patterns.

Inductive reasoning contrasts strongly with deductive reasoning in that, even
in the best, or strongest, cases of inductive reasoning, the truth of the
premises does not guarantee the truth of the conclusion. Instead, the conclusion
of an inductive argument follows with some degree of probability. Relatedly, the
conclusion of an inductive argument contains more information than is already
contained in the premises. Thus, this method of reasoning is ampliative.

A classic example of inductive reasoning comes from the empiricist
David
Hume:

Premise: The sun has risen in the east every morning up until now.

Conclusion: The sun will also rise in the east tomorrow.

[edit]
Abductive reasoning

Main article: abductive
reasoning

Abductive reasoning,
or argument to the best explanation, is a form of inductive reasoning, since the
conclusion in an abductive argument does not follow with certainty from its
premises and concerns something unobserved. What distinguishes abduction from
the other forms of reasoning is an attempt to favour one conclusion above
others, by attempting to falsify alternative explanations or by demonstrating
the likelihood of the favoured conclusion, given a set of more or less
disputable assumptions. For example,
when a patient displays certain symptoms, there might be various possible
causes, but one of these is preferred above others as being more probable.

[edit]
Analogical reasoning

Main article: Analogical
reasoning

Analogical
reasoning is reasoning from the particular to the particular. An example
follows:

Premise 1: Socrates is human and Socrates died.

Premise 2: Plato is human.

Conclusion: Plato will die.

Analogical reasoning can be viewed as a form of inductive reasoning[dubious
– discuss],
since the truth of the premises does not guarantee the truth of the conclusion.
However, the traditional view is that inductive reasoning is reasoning from the
particular to the general, and thus analogical reasoning is distinct from
inductive reasoning.[9]
An example of inductive reasoning from the particular to the general
follows:

Premise 1: Socrates is human and Socrates died.

Premise 2: Plato is human and Plato died.

Premise 3: Aristotle is human and Aristotle died.

Conclusion: All humans die.

It has been argued that deductive, inductive, and abductive reasoning are all
based on a foundation of analogical reasoning.[10]

[edit]
Fallacious reasoning

Main article: Logical fallacy

Flawed reasoning in arguments is known as fallacious reasoning.
Reasoning within arguments can be bad because it commits either a formal
fallacy or an informal fallacy.

[edit]
Formal fallacies

Main article: Formal
fallacy

Formal fallacies occur when there is a problem with the form, or structure,
of the argument. The word "formal" refers to this link to the form of the
argument. An argument that contains a formal fallacy will always be invalid.
Consider, for example, the following argument:

If a drink is made with boiling water, it will be hot.

This drink was not made with boiling water.

This drink is not hot.

The reasoning in this argument is bad, because the antecedent (first part) of
the conditional (the "if...,
then..." statement) can be false without the consequent (second half) of
the conditional being true. In this example, the drink could have been made with
boiling milk, or heated in the microwave, and so be hot in spite of the truth of
statement 2. This particular formal fallacy is known as denying the
antecedent.

[edit]
Informal fallacies

Main article: Informal fallacy

An informal fallacy is an error in reasoning that occurs due to a problem
with the content, rather than mere structure, of the argument.
Reasoning that commits an informal fallacy often occurs in an argument that is
invalid, that is, contains a formal fallacy. One example of such reasoning is a
red herring
argument.

An argument can be valid, that is, contain no formal reasoning fallacies, and
yet still contain an informal fallacy. The clearest examples of this occur when
an argument contains circular reasoning,
also known as begging the
question.

[edit]
Reason,
truth, and "first principles"

Main articles: Truth and First principle

Since classical times a
question has remained constant in philosophical debate (which is sometimes seen
as a conflict between movements called Platonism and Aristotelianism)
concerning the role of reason in confirming truth.

Both Aristotle and Plato, like many philosophers throughout history, wrote
about this question, which can be explained as follows.

People use logic, deduction, and induction, to reach
conclusions they think are true. Conclusions reached in this way are considered
more certain than sense perceptions on their own.[nb
1] On the other hand, if such reasoned conclusions are
only built originally upon a foundation of sense perceptions, then, the argument
being considered goes, our most logical conclusions can never be said to be
certain because they are built upon the very same fallible perceptions they seek
to better.[nb
2]

This leads to the question of what types of first principles, or
starting points of reasoning, are available for someone seeking to come to true
conclusions. Empiricism (sometimes
associated with Aristotle[nb
3] but more correctly associated with British philosophers such
as John
Locke and David Hume, as well as their
ancient equivalents such as Democritus) asserts that
sensory impressions are the only available starting points for reasoning and
attempting to attain truth. This approach always leads to the controversial
conclusion that absolute knowledge is
not attainable. Idealism, (associated with
Plato and his school), claims that there is a "higher" reality, from which
certain people can directly arrive at truth without needing to rely only upon
the senses, and that this higher reality is therefore the primary source of
truth. Whereas secular reason begins with observable reality and applies logic
to it to derive conclusions, theological reason begins with a predetermined
conclusion or unquestionable sacred text and verifies it by using logic to
reinterpret or to reject observable reality.

In Greek, "first principles" are
archē,
"starting points",[nb
4] and the faculty used to perceive them is sometimes
referred to in Aristotle[nb
5] and Plato[nb
6] as nous which was close in meaning
to "awareness" or "consciousness".[nb
7]

Philosophers such as Plato, Aristotle, Al-Farabi, Avicenna, Averroes, Maimonides, Aquinas and Hegel are sometimes
said to have argued that reason must be fixed and discoverable—perhaps by
dialectic, analysis, or study. In the vision of these thinkers, reason is divine
or at least has divine attributes. Such an approach allowed religious
philosophers such as Thomas Aquinas and Étienne Gilson to
try to show that reason and revelation are compatible.
According to Hegel, "...the only thought which Philosophy bring with it to the
contemplation of History, is the simple
conception of reason; that reason is the Sovereign of the World; that the
history of the world, therefore, presents us with a rational process."[11]

Since the 17th century rationalists, reason has
often been taken to be a subjective faculty, or
rather the unaided ability (pure reason) to form
concepts. For Descartes, Spinoza and Leibniz, this was
associated with mathematics. Kant
attempted to show that pure reason could form concepts (time and space) that are the conditions of
experience. Kant made his argument in opposition to Hume, who denied that reason
had any role to play in experience.

[edit]
Justifying reason
itself

Stronger forms of Cartesian
skepticism might well ask "Why use reason?". How a philosopher answers this
question depends on their definition of Truth, particularly their Theory of
justification. Ludwig
Wittgenstein's ordinary
language philosophy would at least have us deconstruct the question, for if
it is taken to mean "What reasons are there to use reason?" then there can be no
non-circular answer - there is no way of reasonably justifying reason. Agree
upon first principles, including laws of logic, are necessary (see above).
Language philosophy might then suggest that the asker is asserting that they
accept the discussion's premise that rationality will be used (although they
unknowingly ask an incoherent question) or else they are denying the premise. Pragmatism
quickly points out the obvious that, if a person actually refuses to use reason,
then rational discussion is impossible.

[edit]
Reason, imagination, mimesis, and memory

Main articles: Imagination, Mimesis, Memory, and Recollection

Reason and imagination rely on similar
mental processes.[12]
Imagination is not only found in humans. But Aristotle, for example, stated that
phantasia (imagination: that which can hold images or phantasmata)
and phronein (a type of thinking which can judge and understand in some
sense) also exist in some animals.[13]
Both are related to the primary perceptive ability of animals, which gathers the
perceptions of different senses and defines the order of the things that are
perceived without distinguishing universals, and without deliberation or
logos. This is equivalent to the habitual thinking about cause and effect
discussed by Hume, and mentioned above. But this is not yet reason, because
human imagination is different.

The recent modern writings of Terrence Deacon and Merlin
Donald fit into an older tradition which makes reason connected to language, and mimesis,[nb
8] but more specifically the ability to create language as part
of an internal modeling of reality specific to humankind.
Other results are consciousness, and imagination or fantasy. In more
recent times, important areas of research include the relationship between
reason and language, especially in discussions of origin of language.
Modern proponents of a
priori reasoning, at least with regards to language, include Noam
Chomsky and Steven Pinker, to whom
Donald and Deacon can be usefully contrasted.

If reason is symbolic thinking, and peculiarly human, then this implies that
humans have a special ability to maintain a clear consciousness of the
distinctness of "icons" or images and the real things they represent. Starting
with a modern author, Merlin Donald writes[14]

A dog might perceive the "meaning" of a fight that was realistically
play-acted by humans, but it could not reconstruct the message or distinguish
the representation from its referent (a real fight). [...] Trained apes are
able to make this distinction; young children make this distinction early –
hence, their effortless distinction between play-acting an event and the event
itself

What Donald refers to here can be compared to Plato's term, eikasia as
explained for example in Jacob Klein's commentary on Plato's dialog concerning
learning, the Meno, which contains a long
digression on this subject.[15]
According to this, an important aspect of human thinking in the Ancient Greek
philosophical terminology of Plato is eikasia. This is the ability to
perceive whether a perception is an image of something else, related somehow but
not the same, and which therefore allows us to perceive that a dream or memory
or a reflection in a mirror is not reality as such. What Klein refers to as
dianoetic eikasia is the eikasia concerned specifically with
thinking and mental images, such as those mental symbols, icons, "signes" and
marks which are discussed above as definitive of reason. Explaining reason from
this direction: human thinking is special in the way that we often understand
visible things as if they were themselves images of our intelligible "objects of
thought" as "foundations" (hypothēses in Ancient Greek). This thinking
(dianoia) is "an activity which consists in making the vast and diffuse
jungle of the visible world depend on a plurality of more 'precise'
noēta".[16]

In turn, both Merlin Donald and the Socratic authors emphasize the importance
of mimesis, often translated as "imitation". Donald writes[17]

Imitation is found especially in monkeys and apes [... but ...] Mimesis is
fundamentally different from imitation and mimicry in that it involves the
invention of intentional representations. [...] Mimesis is not absolutely tied
to external communication.

Mimēsis is a concept, now popular again in academic discussion, which
was particularly prevalent in Plato's works, and within Aristotle, it is
discussed mainly in the Poetics. In Michael Davis's account of the theory
of man in this work.[18]

It is the distinctive feature of human action, that whenever we choose what
we do, we imagine an action for ourselves as though we were inspecting it from
the outside. Intentions are nothing more than imagined actions, internalizings
of the external. All action is therefore imitation of action; it is
poetic...

...Thus Davis is here using "poetic" in an unusual sense, questioning the
contrast in Aristotle between action (praxis, the praktikē) and
making (poēsis, the poētikē)...

...Human [peculiarly human] action is imitation of action because thinking
is always rethinking. Aristotle can define human beings as at once rational
animals, political animals, and imitative animals because in the end the three
are the same.

We can also note that Donald also shares with Plato and Aristotle (especially
in On Memory and Recollection), an emphasis upon the peculiarity in
humans of voluntary initiation of a search through one's mental world. The
ancient Greek anamnēsis, normally translated as "recollection" was
opposed to mneme or "memory". Memory, shared with some animals,[19]
requires a consciousness not only of what happened in the past, but also
that something happened in the past, which is in other words a kind of
eikasia[20]
"but nothing except man is able to recollect".[21]
Recollection is a deliberate effort to search for and recapture something which
was once known. Klein writes that, to "become aware of our having forgotten
something means to begin recollecting".[22]

Donald calls the same thing "autocueing", which he explains as follows:[23]

Mimetic acts are reproducible on the basis of internal, self-generated
cues. This permits voluntary recall of mimetic representations, without the
aid of external cues – probably the earliest form of representational
"thinking".

In a celebrated paper on this subject of modern times, the fantasy author and
philologist J.R.R. Tolkien wrote in
his essay "On Fairy Stories" that the terms "fantasy" and "enchantment" are
connected to not only "the satisfaction of certain primordial human desires" but
also "the origin of language and of the mind".

[edit]
Reason and emotion or
passion

Main articles: Emotion and Passion

In western literature,
reason is often opposed to emotions or feelings—desires, fears, hates,
drives, or passions. Even in everyday speech, westerners tend to say for example
that their passions made them behave contrary to reason, or that their reason
kept the passions under control (often expressed in colloquial terms as the
dilemma between following "the head" (reason) "or the heart" (emotions)) .
Many writers, such as Nikos Kazantzakis,
extol passion and disparage reason.

It has also become common, particularly since the writings of Freud, to describe reason as the
servant of the passions—the means of sorting out our desires and then getting
what we want, or perhaps even the slave of the passions—allowing us to pretend
to reason to the object of our desire. Such feigned reason is called "rationalization".

Philosophers such as Plato, Rousseau, Hume, Kierkegaard, and Nietzsche have combined both
views—making rational thinking not only a tool of desires, but also something
privileged within the spectrum of desires, being itself desired, and not only
because of its usefulness in satisfying other desires.

Modern psychology has much to say on
the role of emotions in belief formation.
Deeper philosophical questions about the relation between belief and reality are
studied in the field of epistemology, which forms
part of the philosophical basis of science, a branch of human
activity that specifically aims to determine (certain types of) truth by methods that avoid
dependence on the emotions of the researchers.

[edit]
Reason in
political philosophy and ethics

Main articles: Political
Philosophy, Ethics, and The Good

Near the beginning of political
philosophy, Aristotle famously described
reason (with language) as a part of human nature which means
that it is best for humans to live "politically" meaning in communities of about
the size and type of a small city state (polis in
Greek). For example...

It is clear, then, that a human being is more of a political
[politikon = of the polis] animal [zōion] than is any bee
or than any of those animals that live in herds. For nature, as we say, makes
nothing in vain, and humans are the only animals who possess reasoned speech
[logos]. Voice, of course, serves to indicate what is painful and
pleasant; that is why it is also found in other animals, because their nature
has reached the point where they can perceive what is painful and pleasant and
express these to each other. But speech [logos] serves to make plain
what is advantageous and harmful and so also what is just and unjust. For it
is a peculiarity of humans, in contrast to the other animals, to have
perception of good and bad, just and unjust, and the like; and the community
in these things makes a household or city [polis]. [...] By nature,
then, the drive for such a community exists in everyone, but the first to set
one up is responsible for things of very great goodness. For as humans are the
best of all animals when perfected, so they are the worst when divorced from
law and right. The reason is that injustice is most difficult to deal with
when furnished with weapons, and the weapons a human being has are meant by
nature to go along with prudence and virtue, but it is only too possible to
turn them to contrary uses. Consequently, if a human being lacks virtue, he is
the most unholy and savage thing, and when it comes to sex and food, the
worst. But justice is something political [to do with the polis], for
right is the arrangement of the political community, and right is
discrimination of what is just. (Aristotle's
Politics 1253a 1.2. Peter Simpson's translation, with Greek terms inserted
in square brackets.)

The concept of human nature being fixed in this way, implied, in other words,
that we can define what type of community is always best for people. This
argument has remained a central argument in all political, ethical and moral
thinking since then, and has become especially controversial since firstly Rousseau's Second Discourse,
and secondly, the Theory of Evolution.
Already in Aristotle there was an awareness that the polis had not always
existed and had needed to be invented or developed by humans themselves. The
household came first, and the first villages and cities were just extensions of
that, with the first cities being run as if they were still families with Kings
acting like fathers.[24]...

Friendship [philia]
seems to prevail [in] man and woman according to nature [kata phusin];
for people are by nature [tēi phusei] pairing [sunduastikon]
more than political [politikon = of the polis], inasmuch as the
household [oikos] is prior [proteron = earlier] and more
necessary than the polis and making children is more common
[koinoteron] with the animals. In the other animals, community
[koinōnia] goes no further than this, but people live together
[sumoikousin] not only for the sake of making children, but also for
the things for life; for from the start the functions [erga] are
divided, and are different [for] man and woman. Thus they supply each other,
putting their own into the common [eis to koinon]. It is for these
[reasons] that both utility [chrēsimon] and pleasure [hēdu] seem
to be found in this kind of friendship. (Nicomachean Ethics,
VIII.12.1162a. Rough literal translation with Greek terms shown in square
brackets.)

Rousseau in his Second
Discourse finally took the shocking step of claiming that this traditional
account has things in reverse: with reason, language and rationally organized
communities all having developed over a long period of time merely as a result
of the fact that some habits of cooperation were found to solve certain types of
problems, and that once such cooperation became more important, it forced people
to develop increasingly complex cooperation—often only in order to defend
themselves from each other.

In other words, according to Rousseau, reason, language and rational
community did not arise because of any conscious decision or plan by humans or
gods, nor because of any pre-existing human nature. As a result, he claimed,
living together in rationally organized communities like modern humans is a
development which has many negative aspects compared to the original state of
man as an ape. If there be anything specifically human in this theory, it is the
flexibility and adaptability of humans. This view of the animal origins of
distinctive human characteristics later received support from Charles Darwin's Theory of
Evolution.

The two competing theories concerning the origins of reason are relevant to
political and ethical thought because according to the Aristotelian theory,
there is a best way of living together which exists independently of historical
circumstances. According to Rousseau, we should even doubt that reason, language
and politics are a good thing, as opposed to being simply the best option given
the particular course of events which lead to today. Rousseau's theory, that
human nature is malleable rather than fixed, is often taken to imply, for
example by Karl Marx, a wider range of
possible ways of living together than traditionally known.

However, while Rousseau's initial impact encouraged bloody revolutions
against traditional politics, including both the French Revolution and
the Russian
Revolution, his own conclusions about the best forms of community seem to
have been remarkably classical, in favor of city-states such as Geneva, and rural living.

[edit]
Reason and faith

Main articles: Faith and Religion

Though theologies and religions
typically do not claim to be irrational, there is often
a perceived conflict or tension between faith and tradition on the one hand, and
reason on the other, as potentially competing sources of wisdom, law and truth. Defenders of traditions and
faiths from claims that they are irrationalist for ignoring or even attempting
to forbid reason and argument concerning some subjects, typically maintain that
there is no real conflict with reason, because reason itself is not enough to
explain such things as the origins of the universe, or right and wrong, and so
reason can and should be complemented by other sources of knowledge. The counter claim
to this is that such a defense does not logically explain why arguments from
reason would be forbidden or ignored.

There are enormously wide differences between different faiths, or even
schools within different faiths, concerning this matter.

Some commentators have claimed that Western civilization can
be almost defined by its serious testing of the limits of tension between
"unaided" reason and faith in "revealed" truths—figuratively
summarized as Athens and Jerusalem, respectively. Leo
Strauss spoke of a "Greater West" which included all
areas under the influence of the tension between Greek rationalism and Abrahamic revelation,
including the Muslim lands. He was particularly
influenced by the great Muslim philosopher Al-Farabi. In order to consider
to what extent Eastern philosophy
might have partaken of these important tensions, it is perhaps best to consider
whether dharma or
tao may be equivalent
to Nature (by which we
mean physis in Greek). According
to Strauss[25]
the beginning of philosophy involved the "discovery or invention of nature" and
the "pre-philosophical equivalent of nature" was supplied by "such notions as
'custom' or 'ways'" which appear to be
"really universal" "in all times and places". The philosophical concept of
nature or natures as a way of understanding archē (first principles of
knowledge) brought about a peculiar tension between reasoning on the one hand,
and tradition or faith on the other.

A Hindu approach
to faith and reason is summarized by Swami Tripurari:

Faith fully understood amounts to conformity to truth, whereas rational
thought is but an imperfect means of apprehending truth. Conforming to truth
involves apprehending or understanding it theoretically, but theoretically
understanding truth does not necessarily involve conforming to it.[26]

[edit]
Psychology

Main article: Psychology of
reasoning

Scientific research into reasoning is carried out within the fields of psychology
and cognitive science.
Psychologists attempt to determine whether or not people are capable of rational
thought in various different circumstances.

Assessing how well someone engages in reasoning is the project of determining
the extent to which the person is rational or acts rationally.
It is a key research question in the psychology of
reasoning. Rationality is often divided
into its respective theoretical
and practical counterparts.

[edit]
Behavioral
experiments on human reasoning

Experimental cognitive psychologists carry out research on reasoning
behaviour. Such research may focus, for example, on how people perform on tests
of reasoning such as intelligence or IQ tests,
or on how well people's reasoning matches ideals set by logic (see, for example,
the Wason test).[27]
Experiments examine how people make inferences from conditionals e.g., If A
then B and how they make inferences about alternatives, e.g., A or else
B.[28]
They test whether people can make valid deductions about spatial and temporal
relations, e.g., A is to the left of B, or A happens after B, and
about quantified assertions, e.g., All the A are B.[29]
Experiments investigate how people make inferences about factual situations,
hypothetical possibilities, probabilities, and counterfactual
situations.[30]

[edit]
Developmental studies of children's reasoning

Developmental psychologists investigate the development of reasoning from
birth to adulthood. Piaget's theory of
cognitive development was the first complete theory of reasoning
development. Subsequently, several alternative theories were proposed, including
the neo-Piagetian
theories of cognitive development.[31]

[edit]
Neuroscience of
reasoning

The biological functioning of the brain is studied by neurophysiologists and
neuropsychologists.
Research in this area includes research into the structure and function of
normally functioning brains, and of damaged or otherwise unusual brains. In
addition to carrying out research into reasoning, some psychologists, for
example, clinical
psychologists and psychotherapists work
to alter people's reasoning habits when they are unhelpful.

[edit]
Automated reasoning

Main articles: Automated reasoning
and Computational
logic

In artificial
intelligence and computer science,
scientists study and use automated reasoning
for diverse applications including automated theorem
proving the formal
semantics of programming languages, and formal
specification in software
engineering.

[edit]
Meta-reasoning

Main article: Metacognition

Meta-reasoning is reasoning about reasoning. In computer science, a system
performs meta-reasoning when it is reasoning about its own operation.[32]
This requires a programming language capable of reflection,
the ability to observe and modify its own structure and behaviour.

[edit]
See also

Thinking
portal

Logic
portal

Calculation

Conscience

Consciousness

Deism

Empiricism

Epistemology

Intellect

Inquiry

Knowledge

Fantasy

Fideism

Foucault/Habermas
debate

Language

Logic

Mimesis

Mind

Nous

Practical reason

Rationality

Rationality and
power

Speculative reason

Truth

[edit]
Further reading

Look up reason in Wiktionary, the free
dictionary.

Wikiquote has a
collection of quotations related to: Reason

Beer, Francis A., "Words of Reason", Political Communication 11
(Summer, 1994): 185-201.

Gilovich, Thomas
(1991), How We Know What Isn't So: The Fallibility of Human Reason in
Everyday Life, New York: The Free Press, ISBN 0-02-911705-4

Tripurari, Swami,
On Faith
and Reason, The Harmonist, May 27, 2009.

[edit]
References

^ Merriam-Webster.com Merriam-Webster Dictionary definition of
reason

^ Aristotle,
Complete Works (2 volumes), Princeton, 1995, ISBN
0-691-09950-2

^ See this Perseus search, and compare English translations.
and see LSJ dictionary entry for λογικός, section II.2.b.

^ Douglas
Hofstadter, Gödel, Escher, Bach, Vintage, 1979, ISBN
0-394-74502-7

^ See the Treatise of Human
Nature of David Hume, Book I, Part
III, Sect. XVI

^ Terrence
Deacon, The Symbolic Species: The Co-Evolution of Language and the
Brain, W.W. Norton & Company, 1998, ISBN
0-393-31754-4

^ Leviathan Chapter IV: "The Greeks have but one word, logos,
for both speech and reason; not that they thought there was no speech without
reason, but no reasoning without speech"

^ Jeffrey,
Richard. 1991. Formal logic: its scope and limits, (3rd ed.). New York:
McGraw-Hill:1.

^ Vickers, John,
"The Problem of Induction", The Stanford Encyclopedia of Philosophy, 2009, http://plato.stanford.edu/entries/induction-problem/

^ John F. Sowa
and Arun K. Majumdar, Analogical Reasoning, in de Moor, Lex, Ganter, eds.,
Conceptual Structures for Knowledge Creation and Communication, Proceedings of
ICCS 2003, LNAI 2746, Springer-Verlag, Berlin, 2003, pp. 16-36. http://www.jfsowa.com/pubs/analog.htm

^ G.W.F. Hegel
The
Philosophy of History, p. 9, Dover Publications Inc., ISBN
0-486-20112-0; 1st ed. 1899

^ See for
example Ruth M.J. Byrne
(2005). The Rational Imagination: How People Create Counterfactual
Alternatives to Reality. Cambridge, MA: MIT Press.

^ De Anima III.i-iii; On
Memory and Recollection, On Dreams

^ Origins of
the Modern Mind p.172

^ Ch.5

^ Jacob Klein
A Commentary on the Meno p.122

^ Origins of
the Modern Mind p.169

^
"Introduction" to the translation of Poetics by
Davis and Seth Benardete p. xvii,
xxviii

^ Aristotle On Memory
450a 15-16.

^ Klein p.109

^ Aristotle
Hist. Anim. I.1.488b.25-26.

^ Jacob Klein
A Commentary on the Meno p. 112

^ The
Origins of the Modern Mind p.173 see also A Mind So Rare p.140-1

^ Politics
I.2.1252b15

^ "Progress or
Return" in An Introduction to Political Philosophy: Ten Essays by Leo Strauss.
(Expanded version of Political Philosophy: Six Essays by Leo Strauss, 1975.)
Ed. Hilail Gilden. Detroit: Wayne State UP, 1989.

^ Tripurari, Swami, On Faith and Reason, The Harmonist, May 27,
2009.

^ Manktelow,
K.I. 1999. Reasoning and Thinking (Cognitive Psychology: Modular
Course.). Hove, Sussex:Psychology Press

^
Johnson-Laird, P.N. & Byrne, R.M.J. (1991). Deduction. Hillsdale:
Erlbaum

^
Johnson-Laird, P.N. (2006). How we reason. Oxford: Oxford University
Press

^ Byrne, R.M.J.
(2005). The Rational Imagination: How People Create Counterfactual
Alternatives to Reality. Cambridge, MA: MIT Press

^ Demetriou, A.
(1998). Cognitive development. In A. Demetriou, W. Doise, K.F.M. van Lieshout
(Eds.), Life-span developmental psychology (pp. 179-269). London: Wiley.

^ doi:10.1007/3-540-45632-5_11

[edit]
Footnotes

^ Example:
Metaphysics 981b: τὴν ὀνομαζομένην σοφίαν περὶ τὰ πρῶτα αἴτια καὶ τὰς ἀρχὰς
ὑπολαμβάνουσι πάντες: ὥστε, καθάπερ εἴρηται πρότερον, ὁ μὲν ἔμπειρος τῶν
ὁποιανοῦν ἐχόντων αἴσθησιν εἶναι δοκεῖ σοφώτερος, ὁ δὲ τεχνίτης τῶν ἐμπείρων,
χειροτέχνου δὲ ἀρχιτέκτων, αἱ δὲ θεωρητικαὶ τῶν ποιητικῶν μᾶλλον. "...what is
called Wisdom is concerned with the primary causes and principles, so that, as
has been already stated, the man of experience is held to be wiser than the
mere possessors of any power of sensation, the artist than the man of
experience, the master craftsman than the artisan; and the speculative
sciences to be more learned than the productive."

^ Metaphysics
1009b ποῖα οὖν τούτων ἀληθῆ ἢ ψευδῆ, ἄδηλον: οὐθὲν γὰρ μᾶλλον τάδε ἢ τάδε
ἀληθῆ, ἀλλ᾽ ὁμοίως. διὸ Δημόκριτός γέ φησιν ἤτοι οὐθὲν εἶναι ἀληθὲς ἢ ἡμῖν γ᾽
ἄδηλον. "Thus it is uncertain which of these impressions are true or false;
for one kind is no more true than another, but equally so. And hence
Democritus says1 that either there is no truth or we cannot discover it."

^ However, the
empiricism of Aristotle must certainly be doubted. For example in Metaphysics
1009b, cited above, he criticizes people who think knowledge might not be
possible because "they say that the impression given through sense-perception
is necessarily true; for it is on these grounds that both Empedocles and
Democritus and practically all the rest have become obsessed by such opinions
as these".

^ For example
Aristotle Metaphysics 983a: ἐπεὶ δὲ φανερὸν ὅτι τῶν ἐξ ἀρχῆς
αἰτίων δεῖ λαβεῖν ἐπιστήμην （τότε γὰρ εἰδέναι φαμὲν ἕκαστον, ὅταν τὴν
πρώτην αἰτίαν οἰώμεθα γνωρίζειν） "It is clear that we must
obtain knowledge of the primary causes, because it is when we think
that we understand its primary cause that we claim to know each
particular thing."

^ Example:
Nicomachean Ethics 1139b: ἀμφοτέρων δὴ τῶν νοητικῶν μορίων
ἀλήθεια τὸ ἔργον. καθ᾽ ἃς οὖν μάλιστα ἕξεις ἀληθεύσει ἑκάτερον, αὗται ἀρεταὶ
ἀμφοῖν. The attainment of truth is then the function of both the
intellectual parts of the soul. Therefore their respective virtues are
those dispositions which will best qualify them to attain truth.

^ Example:
Plat. Rep. 490b μιγεὶς τῷ ὄντι ὄντως, γεννήσας νοῦν καὶ ἀλήθειαν, γνοίη
"consorting with reality really, he would beget intelligence and truth, attain
to knowledge"

^ "This quest
for the beginnings proceeds through sense perception, reasoning, and what they
call noesis, which is literally translated by "understanding" or
intellect," and which we can perhaps translate a little bit more cautiously by
"awareness," an awareness of the mind's eye as distinguished from sensible
awareness." "Progress or Return" in An Introduction to Political Philosophy:
Ten Essays by Leo Strauss. (Expanded version of Political Philosophy: Six
Essays by Leo Strauss, 1975.) Ed. Hilail Gilden. Detroit: Wayne State UP,
1989.

^ It should be
noted that mimesis in modern academic writing, starting with Erich Auerbach, is a
technical word, which is not necessarily exactly the same in meaning as the
original Greek. See Mimesis.

v • d • e

Figures in the Age of
Enlightenment by country or region

Notable figures

America
(English)

Benjamin
Franklin · Thomas
Jefferson · James
Madison · Thomas
Paine

America (Latin)

Simón
Bolívar  · Eugenio
Espejo  · José
Joaquín Fernández de Lizardi ·
Servando
Teresa de Mier · Francisco
de Miranda · Simón
Rodríguez

England

Edward
Gibbon · Thomas
Hobbes  · Samuel
Johnson · Edmund
Burke (Irish born)  · John
Locke  · Isaac
Newton  · Robert
Walpole

France

Montesquieu ·
François
Quesnay · Voltaire ·
Buffon ·
Jean-Jacques
Rousseau · Denis
Diderot · Helvétius ·
Jean
le Rond d'Alembert · Baron
d'Holbach · Condorcet ·
Étienne
Bonnot de Condillac

Germany

Immanuel
Kant · Gotthold
Ephraim Lessing · Johann
Gottfried von Herder · Johann
Wolfgang von Goethe · Friedrich
Schiller · Moses
Mendelssohn

Greece

Adamantios
Korais · Rigas
Feraios · Theophilos
Kairis · Eugenios
Voulgaris

Hungary

Ferenc
Kazinczy · József
Kármán · János
Batsányi · Mihály
Fazekas

Italy

Cesare
Beccaria · Antonio
Genovesi

Low Countries

Hugo
Grotius · Baruch
Spinoza · Franciscus
van den Enden

Poland-Lithuania

Stanisław
Konarski · Ignacy
Krasicki · Hugo
Kołłątaj · Stanisław
Staszic · Jan
Śniadecki · Julian
Ursyn Niemcewicz · Jędrzej
Śniadecki

Portugal

Sebastião
José de Carvalho e Melo, Marquis of
Pombal

Russia

Mikhail
Lomonosov · Ivan
Shuvalov · Ivan
Betskoy · Ekaterina
Dashkova · Nikolay
Novikov · Mikhail
Shcherbatov · Alexander
Radishchev

Scandinavia

Anders
Chydenius · Peter
Forsskål · Gustav
III · Ludvig
Holberg · Arvid
Horn · Johan
Henric Kellgren · Eggert
Ólafsson  · Henrik
Gabriel Porthan · Jens
Schielderup Sneedorff · Johann
Friedrich Struensee · Emanuel
Swedenborg

Scotland

Joseph
Black · James
Boswell · Robert
Burns · Adam
Ferguson · Francis
Hutcheson · David
Hume · James
Hutton · Lord
Kames · Lord
Monboddo · James
Macpherson · Thomas
Reid · William
Robertson · Adam
Smith · Dugald
Stewart · James
Watt

Serbia

Dositej
Obradović

Spain

Gaspar
Melchor de Jovellanos · Benito
Jerónimo Feijoo · Antonio
de Ulloa

Ukraine

Hryhorii
Skovoroda · Ivan
Kotlyarevsky

Related topics

Atheism ·
Capitalism ·
Civil
liberties · Counter-Enlightenment ·
Critical
thinking · Deism ·
Democracy ·
Empiricism ·
Enlightened
absolutism · Free
markets · Haskalah ·
Humanism ·
Liberalism ·
Natural
philosophy · Rationality ·
Reason ·
Sapere
aude · Science ·
Socialism ·
Secularism ·
French
Encyclopédistes · Weimar
Classicism

v • d • e

Logic

Related articles

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Critical
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theory · Formal
semantics · History
of logic · Informal
logic · Logic
in computer science · Mathematical
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Metalogic ·
Metamathematics ·
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theory · Philosophical
logic · Philosophy ·
Philosophy
of logic · Philosophy
of mathematics · Proof
theory · Set
theory

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A
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Retrieved from "http://en.wikipedia.org/wiki/Reason"

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