Philosophy considers it is an act by which the mind perceives the agreement or disagreement of two ideas. When using only intuition, the truth of the proposition is immediately known right then, the moment it is presented. This is without the intervention of other ideas or deductive reasoning.
In common usage, intuitions lead us to believe things without being able to articulate evidence or reasons for those beliefs. In philosophy, the epistemic credentials of various types of intuition may be investigated, or "intuition" may be used as a technical term to single out a particular type of mental state or propositional attitude. Intuitions are distinguished from beliefs, since we can hold beliefs which are not intuitive, or have intuitions for propositions that we know to be false.
In the philosophy of Immanuel Kant, intuition is one of the basic cognitive faculties, equivalent to what might loosely be called perception. Kant held that our mind casts all of our external intuitions in the form of space, and all of our internal intuitions (memory, thought) in the form of time.
"Intuitionism" is a position advanced in philosophy of mathematics derived from Kant's claim that all mathematical knowledge is knowledge of the pure forms of the intuition - that is, intuition that is not empirical (Prolegomena, p.7). Intuitistic logic was devised by Arend Heyting to accommodate this position (and has been adopted by other forms of [constructivism in general). It is characterized by rejecting the law of excluded middle: as a consequence it does not in general accept rules such as double negation elimination and the use of reductio ad absurdum to prove the existence of something.
In analytic philosophy
In contemporary analytic philosophy, appeals to our intuitions are an important method for testing claims. A characteristic example is the post-Gettier literature concerning the analysis of knowledge. A philosopher proposes a definition of knowledge, such as the justified true belief account. Another philosopher constructs a hypothetical case where our inclination is to judge that the definition is met but the subject lacks knowledge or vice versa. Typically, this leads to the rejection of that account, though Brian Weatherson has noted that the weight placed on intuitions varies between different subfields.
Intuitions are customarily appealed to independently of any particular theory of how intuitions provide evidence for claims, and there are divergent accounts of what sort of mental state intuitions are, ranging from mere spontaneous judgment to a special presentation of a necessary truth. However, in recent years a number of philosophers have tried to defend appeals to intuition against doubts about conceptual analysis. A different challenge to appeals to intuition has recently come from experimental philosophers, who argue that appeals to intuition must be informed by the methods of social science.
- AJ Giannini, J Daood,MC Giannini, R. Boniface, PG Rhodes. Intellect versus intuition--a dichotomy in the reception of nonverbal communication Journal of General Psychology. 99:19-24, 1978.
- American International Encyclopedia, J.J. Little Co., New York 1954, Vol VIII
- B. Weatherson, "What Good are Counterexamples?", Philosophical Studies, 115 (2003) pp. 1-31.
- M. Lynch "Trusting Intuitions", in P. Greenough and M. Lynch (ed) Truth and Realism, pp. 227-38.
- G. Bealer "Intuition and The Autonomy of Philosophy" in M. Depaul and W. Ramsey (eds) Rethinking Intuition: The Psychology of Intuition and Its Role In Philosophical Inquiry 1998, pp. 201-239.
- A selection of articles defining the nature of Intuition
- Essay about the philosophical and psychological dimensions of four types of intuition
- A scientific research group on intuition
- Ask Philosophers: Question on Intuition and Rationality
- Hypothesis: Improving Left brain Intuition/Innovation
- Intuition as a 'feeling'
- http://LBIndy.com/Unleash the Power of Your Intuition column