Necessitarian adj. Of or pertaining to the doctrine of philosophical necessity in regard to the origin and existence of things, especially as applied to the actings or choices of the will; opposed to libertarian.
... the essentials of the book as a contribution to biological philosophy. The closing chapters contain a lucid statement of objections to his theory as they might be put by a rigid necessitarian, and a refutation of that interpretation as applied ... — Unconscious Memory • Samuel Butler
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