philosophy of science Philosophy of science is the branch of philosophy concerned with the foundations, methods, and implications of science. Amongst its central questions are the difference between science and non-science, the reliability of scientific theories, ...

, intertheoretic reduction occurs when a reducing theory makes predictions that perfectly or almost perfectly match the predictions of a reduced theory, while the reducing theory explains or predicts a wider range of phenomena under more general conditions.

Special relativity In physics, the special theory of relativity, or special relativity for short, is a scientific theory of the relationship between Spacetime, space and time. In Albert Einstein's 1905 paper, Annus Mirabilis papers#Special relativity, "On the Ele ...

, for example, can be reduced to

Newtonian mechanics Newton's laws of motion are three physical laws that describe the relationship between the motion of an object and the forces acting on it. These laws, which provide the basis for Newtonian mechanics, can be paraphrased as follows: # A body r ...

for speeds far less than '' c''. According to

Alexander Rosenberg Alexander Rosenberg (who generally publishes as "Alex") is an American philosopher and novelist. He is the R. Taylor Cole Professor of Philosophy at Duke University, well known for contributions to philosophy of biology and philosophy of econ ...

philosophers mostly these days believe that reduction between sciences is possible ''in principle'' but concepts we currently have do not allow reductions even in many cases in which

natural science Natural science or empirical science is one of the branches of science concerned with the description, understanding and prediction of natural phenomena, based on empirical evidence from observation and experimentation. Mechanisms such as peer ...

s are involved, for instance from

biology Biology is the scientific study of life and living organisms. It is a broad natural science that encompasses a wide range of fields and unifying principles that explain the structure, function, growth, History of life, origin, evolution, and ...

chemistry Chemistry is the scientific study of the properties and behavior of matter. It is a physical science within the natural sciences that studies the chemical elements that make up matter and chemical compound, compounds made of atoms, molecules a ...

. Often, the extent to which one theory can be said to be reduced to another theory is complicated by the existence of emergent phenomena. Furthermore, there is the issue of by what criteria one judges one theory as more fundamental than another. Often, this notion is ambiguous. For instance, a quintessential example of intertheoretic reduction is often considered to be the reduction of phenomenological thermodynamics to

statistical mechanics In physics, statistical mechanics is a mathematical framework that applies statistical methods and probability theory to large assemblies of microscopic entities. Sometimes called statistical physics or statistical thermodynamics, its applicati ...

. However, it has been argued that there are some phenomena (e.g.

phase transition In physics, chemistry, and other related fields like biology, a phase transition (or phase change) is the physical process of transition between one state of a medium and another. Commonly the term is used to refer to changes among the basic Sta ...

s and critical phenomena) that cannot be reductively explicated in terms of the "more fundamental" theory of statistical mechanics. Especially

psychology Psychology is the scientific study of mind and behavior. Its subject matter includes the behavior of humans and nonhumans, both consciousness, conscious and Unconscious mind, unconscious phenomena, and mental processes such as thoughts, feel ...

is seen often as a "scientific dead-end" due to its intentional concepts (though psychology does not necessarily have to use intentional concepts). Logical analysis has suggested that intentional concepts are not reducible to non-intentional concepts used by

neurophysiology Neurophysiology is a branch of physiology and neuroscience concerned with the functions of the nervous system and their mechanisms. The term ''neurophysiology'' originates from the Greek word ''νεῦρον'' ("nerve") and ''physiology'' (whic ...

in which is the discipline "underlying" the psychology.Rosenberg's book, chapter 2

References

{{Philosophy of science Metatheory of science Reductionism