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metaphysics

The Four Causes

αἰτίαι

Four answers to 'why?' — what a thing is made of, its form, what brought it about, and its purpose.

Also: material cause · formal cause · efficient cause · final cause · aition

Aristotle identified four distinct types of cause (aitiai) to fully explain any object or event. The material cause is the physical substance something is made from; the formal cause is its essential shape or definition; the efficient cause is what brings it into being or sets it in motion; and the final cause is its purpose or end goal. Together, these four causes provide complete explanations rather than partial ones, distinguishing Aristotle's approach from earlier philosophers who focused mainly on material composition.

Consider a bronze statue: the material cause is the bronze itself; the formal cause is the particular shape the sculptor envisions; the efficient cause is the sculptor's skill and labor; and the final cause is its purpose—perhaps to honor a god. A complete account requires all four, not just noting it is made of bronze. This framework became foundational to Western philosophy and shaped how thinkers approached questions about existence and change for centuries.

The Four-Cause framework was adopted by the medieval Arabic falsafa (Ibn Sina), Maimonides (*Guide* I.69 on God as the formal, efficient, and final cause of being), and Aquinas — whose *quinque viae* depend on the chain-of-efficient-causes argument. Bacon, Spinoza, and Hume's collapse of final causation later challenged the scheme; modern philosophy of science has partially rehabilitated Aristotelian causal explanation (Ellis, Cartwright).

Where this idea shows up

49 Greek sources·3 Jewish-canon citations

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