Organicism as a doctrine rejects mechanism and
reductionism (doctrines that claim that the smallest parts by themselves explain the behavior of larger organized systems of which they are a part). However, organicism also rejects
vitalism, the doctrine that there is a vital force different from physical forces that accounts for living things. As Fritjof Capra puts it, both schools, organicism and vitalism, were born from the quest for getting rid of the Cartesian picture of reality, a view that has been claimed to be the most destructive paradigm nowadays, from science to politics. A number of biologists in the early to mid-twentieth century embraced organicism. They wished to reject earlier vitalisms but also to stress that whole organism biology was not fully explainable by atomic mechanism. The larger organization of an organic system has features that must be taken into account to explain its behavior. The French zoologist
Yves Delage, in his seminal text ''L'Hérédité Et Les Grands Problèmes de la Biologie Générale,'' described organicism thus: [L]ife, the form of the body, the properties and characters of its diverse parts, as resulting from the reciprocal play or struggle of all its elements, cells, fibres, tissues, organs, which act the one on the other, modify one the other, allot among them each its place and part, and lead all together to the final result, giving thus the appearance of a consensus, or a pre-established harmony, where in reality there is nothing but the result of independent phenomena.
Scott F. Gilbert and
Sahotra Sarkar distinguish organicism from holism to avoid what they see as the vitalistic or spiritualistic connotations of holism. Still more independence is present in relational holism. This doctrine does not assert top-down control of the whole over its parts, but does claim that the relations of the parts are essential to explanation of behavior of the system. Aristotle and early modern philosophers and scientists tended to describe reality as made of substances and their qualities, and to neglect relations.
Gottfried Wilhelm Leibniz showed the bizarre conclusions to which a doctrine of the non-existence of relations led. Twentieth century philosophy has been characterized by the introduction of and emphasis on the importance of relations, whether in
symbolic logic, in
phenomenology, or in metaphysics.
William Wimsatt has suggested that the number of terms in the relations considered distinguishes reductionism from holism. Reductionistic explanations claim that two or at most three term relations are sufficient to account for the system's behavior. At the other extreme the system could be considered as a single ten to the twenty-sixth term relation, for instance. == In theology ==