Reductionism

Reductionism in philosophy describes a number of related, contentious theories that hold, very roughly, that the nature of complex things can always be reduced to (be explained by) simpler or more fundamental things. This is said of objects, phenomena, explanations, theories, and meanings. In short, it is philosophical materialism taken to its logical consequences.

Roughly this means that chemistry is based on physics, biology is based on chemistry, psychology and sociology are based on biology. The first of these are commonly accepted but the last step is controversial and therefore the frontier of reductionism: evolutionary -psychology and -sociology vs. those who claim people have a soul or another quality that separates them from the material world. Reductionists believe that the behavioral-sciences should become a genuine scientific discipline by being based on genetic biology.

A very typical reductionistic book is The Selfish Gene by Richard Dawkins. It argues that because genes are the fundamental elements of life, all life and all natural behavior can best be understood by studying genetic mechanisms. This way all life is best regarded as temporary accommodation and a reproduction device for the genes.

In his book The Blind Watchmaker, Dawkins introduced the term "hierarchic reductionism". This means that reductionism can only work when it is used one level at a time. For example: when you throw Stephen Gould out of a window, his fall can be explained by classic mechanics. But you should not try to understand his work from such elementary principles.

(The term is also sometimes used to criticize an imagined position rather than to describe a real one.)

• Ontological reductionism is the idea that everything that exists is made from a small number of basic substances that behave in regular ways. Compare to monism.
• Methodological reductionism is the idea that explanations of things, such as scientific explanations, ought to be continually reduced to the very simplest entities possible (but no simpler). Occam's Razor forms the basis of this type of reductionism.
• Theoretical reductionism is the idea that older theories or explanations are not generally replaced outright by new ones, but that new theories are refinements or reductions of the old theory in greater detail.
• Scientific reductionism has been used to describe all of the above ideas as they relate to science, but is most often used to describe the idea that all phenomena can be reduced to scientific explanations.
• Linguistic reductionism is the idea that everything can be described in a language with a limited number of core concepts, and combinations of those concepts. (See Basic English and the constructed language Toki Pona).
• The term "greedy reductionism" was coined by Daniel Dennett to condemn those forms of reductionism that try to explain too much with too little.
• Analytical reductionism as used in "Is Reductionism A Good Approach In Science?" "is the underlying a priori of ontological reductionism".

The denial of reductionist ideas is holism; the idea that things can have properties as a whole that are not explainable from the properties of their parts. Phenomena such as emergence and work within the field of complex systems theory is considered to bring forth possible objections to reductionism.