Holism and holistic are terms coined by Jan Smuts in the early 1920s.

Smuts' definition of holism, as given in the Oxford English Dictionary, reads: "The tendency in nature to form wholes, that are greater than the sum of the parts, through creative evolution."

As currently understood, holism is the idea that the properties of a system cannot be determined or explained by the sum of its components alone. It is often regarded as opposite to reductionism, although proponents of scientific reductionism state that it is better regarded as the opposite of greedy reductionism.

Examples

Physics: Certain quantum phenomena seem to arise only in systems and cannot be explained by the interaction of the system's individual parts alone. This is a suggestion, not a fact or law.

Metaphysics: Phenomena such as life, mind and conscience only arise in systems. This means these things cannot be explained by the study of nerves, cells or atoms. Many religions take a holistic approach to consciousness.

One theory of holism is based on the hypothesis that nature consists of a hierarchy of "wholes" (also called "holons", a term created by Arthur Koestler). These "wholes" are quarks, protons, atoms, molecules, minerals, cellss, tissuess, organisms, populations.

Hence, a large-scale body, such as the biosphere cannot be understood by only studying the elements, but should be considered as a whole entity, studied through the different hierarchical levels, and with the different relations between the different elements.

However, holism also means an object or a system can be recognised as a type, only with a few well-chosen characteristics. Hence, it is the basis of classification or typology. Soil, vegetation (land cover), biomes are commonly considered as wholes and hence can be classified using a set of diagnostic charateristics (see for example land classification).

The field of systems thinking has been developed in recent years to tackle a wide range of issues using holistic concepts.

See also