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Aristotle's four causes
c. 350–330 BC· Idea or argument· Reality, mind & God
Well documentedSolid records, texts or physical evidence.
Aristotle's claim that fully explaining anything means answering four questions: what it is made of, its form, its maker, and its purpose.
See it on the Philosophy map →The idea
The idea: a single 'cause' never explains enough. Aristotle's example is a bronze statue. Its material cause is the bronze; its formal cause, the shape that makes it this statue; its efficient cause, the sculptor; its final cause, its purpose, perhaps honouring a god. He applied the same scheme to nature: an acorn's final cause is the oak it grows into. The Greek word aitia means 'explanation'. The main objection: modern science dropped purposes from physics, and Darwin explained apparent design without one.
Why it matters
It structured science and theology until the 1600s, including Aquinas's Five Ways, and the question of purpose in nature is still alive in biology.
Think of it like
A building project has all four: the materials, the architect's plans, the contractor, and the business case it was built for.
Where it comes from
Set out in Physics Book II and Metaphysics Book I, in the body of works edited by Andronicus of Rhodes in the 1st century BC.
Still debated
Biologists still argue whether saying what an organ is 'for' is shorthand for evolutionary history or a genuine kind of explanation.
Connections (2)
▸Aristotle proposed Aristotle's four causesWell documented
The connection
Aristotle saw earlier thinkers each grabbing one kind of explanation: the Presocratics stressed what things are made of, Plato stressed form. He combined them, added the maker and the purpose, and argued that a full scientific explanation of anything, from a statue to a heart, answers all four questions.
When and how
Athens, in the Physics and Metaphysics, probably written or revised at the Lyceum around 335–322 BC.
How we know
Physics Book II and Metaphysics Book I state the four causes and review how earlier philosophers had each caught only part of them.
Debates and open questions
Whether final causes in nature mean real purposes or just regular outcomes, like teeth growing in a way suited to chewing, is debated among Aristotle scholars.
▸Aristotle's four causes underpin Aquinas' Five WaysMostly agreed
The connection
The Five Ways reason with Aristotle's types of explanation. The first two use efficient causes, what brings change about, to argue back to a first mover and a first cause. The fifth uses final causes, the goals things naturally tend toward, to argue that something intelligent directs nature.
When and how
Summa Theologiae, written about 1266–1268 in Rome; Aquinas drew on Aristotle's Physics and Metaphysics, where the unmoved mover first appears some 1,600 years earlier.
How sure are we?
The texts line up closely: the First Way restates the argument for an unmoved mover in Aristotle's Physics, Book VIII, on which Aquinas wrote a commentary.
Debates and open questions
Whether the Five Ways survive the loss of Aristotle's physics, such as his claim that every motion needs a mover, is still argued by philosophers of religion.