The principle of
Irreducibility, in
philosophyPhilosophy is the study of general and fundamental problems concerning matters such as existence, knowledge, values, reason, mind, and language. Philosophy is distinguished from other ways of addressing these questions by its critical, generally systematic approach and its reliance on reasoned...
, has the sense that a complete account of an
entityAn entity is something that has a distinct, separate existence, though it need not be a material existence. In particular, abstractions and legal fictions are usually regarded as entities. In general, there is also no presumption that an entity is animate...
will not be possible at lower levels of explanation and which has novel properties beyond prediction and explanation. Another way to state this is that
Occam's razorOccam's razor , entia non sunt multiplicanda praeter necessitatem , is the principle that can be popularly stated as "when you have two competing theories that make exactly the same predictions, the simpler one is the better." The principle is attributed to 14th-century English...
requires the elimination of only those entities that are unnecessary, not as many entities as could conceivably be eliminated.
Lev VygotskyLev Semyonovich Vygotsky was a Soviet psychologist and the founder of cultural-historical psychology.- Biography :...
provides the following illustration of the idea, in his
Thought and Language:
- "Two essentially different modes of analysis are possible in the study of psychological
Psychology is an academic and applied discipline involving the systematic, and sometimes scientific, study of human or animal mental functions and behavior...
structures.
The principle of
Irreducibility, in
philosophyPhilosophy is the study of general and fundamental problems concerning matters such as existence, knowledge, values, reason, mind, and language. Philosophy is distinguished from other ways of addressing these questions by its critical, generally systematic approach and its reliance on reasoned...
, has the sense that a complete account of an
entityAn entity is something that has a distinct, separate existence, though it need not be a material existence. In particular, abstractions and legal fictions are usually regarded as entities. In general, there is also no presumption that an entity is animate...
will not be possible at lower levels of explanation and which has novel properties beyond prediction and explanation. Another way to state this is that
Occam's razorOccam's razor , entia non sunt multiplicanda praeter necessitatem , is the principle that can be popularly stated as "when you have two competing theories that make exactly the same predictions, the simpler one is the better." The principle is attributed to 14th-century English...
requires the elimination of only those entities that are unnecessary, not as many entities as could conceivably be eliminated.
Lev VygotskyLev Semyonovich Vygotsky was a Soviet psychologist and the founder of cultural-historical psychology.- Biography :...
provides the following illustration of the idea, in his
Thought and Language:
- "Two essentially different modes of analysis are possible in the study of psychological
Psychology is an academic and applied discipline involving the systematic, and sometimes scientific, study of human or animal mental functions and behavior...
structures. It seems to us that one of them is responsible for all the failures that have beset former investigators of the old problem, which we are about to tackle in our turn, and that the other is the only correct way to approach it.
- The first method analyzes complex psychological wholes into "elements". It may be compared to the chemical analysis of water into hydrogen
Hydrogen is the chemical element with atomic number 1. It is represented by the symbol H. At standard temperature and pressure, hydrogen is a colorless, odorless, nonmetallic, tasteless, highly flammable diatomic gas with the molecular formula H
2...
and oxygenOxygen Oxygen Oxygen (acid, literally "sharp", from the taste of acids) and -γενής (-genēs) (producer, literally begetter) is the element with atomic number 8 and represented by the symbol O...
, neither of which possesses the properties of the whole and each of which possesses properties not present in the whole. The student applying this method in looking for an explanation of some property of water — why it extinguishes fire, for example — will find to his surprise that hydrogen burns and oxygen sustains fire ....
- In our opinion the right course to follow is to use the other type of analysis, which may be called "analysis into units". By "unit", we mean a product of analysis which, unlike elements, retains all the basic properties of the whole, and which cannot be further divided without losing them. Not the chemical composition of water, but its molecules and their behaviour, are the key to the understanding of the properties of water ..."
In other words: to conserve the properties under investigation, it is necessary to remain within a certain level of complexity. Irreducibility is most often deployed in defence of the reality of human
subjectivitySubjectivity refers to a person's perspective or opinion, particular feelings, beliefs, and desires. It is often used casually to refer to unsubstantiated personal opinions, in contrast to knowledge and fact-based beliefs. In philosophy, the term is often contrasted with...
and/or
free willFree will raises the question whether, and in what sense, rational agents exercise control over their actions, decisions, choices. Addressing this question requires understanding the relationship between freedom and cause, and determining whether the laws of nature are causally deterministic...
, against those who treat such things as
folk psychologyFolk psychology is the set of assumptions, constructs, and convictions that makes up the everyday language in which people discuss human psychology...
, such as
PaulPaul Churchland is a philosopher noted for his studies in neurophilosophy and the philosophy of mind. He is currently a Professor at the University of California, San Diego, where he holds the Valtz Chair of Philosophy. Churchland holds a joint appointment with the Cognitive Science Faculty and the...
and
Patricia ChurchlandPatricia Smith Churchland is a Canadian-American philosopher working at the University of California, San Diego since 1984...
.