The Lagoon: How Aristotle Invented Science

by Armand Marie Leroi

The whole problem was that none of his predecessors saw that natures could be, should be, understood in several different ways. Our hearts beat – but not just because of chemistry; nor just to keep us alive; nor just because one grew in our embryonic torsos; nor even just because our parents had hearts too; rather, our hearts beat because of all of these things. All these kinds of causes complement each other, indeed, are deeply intertwined. Or so Aristotle argues in a famous methodological dictum known as the ‘four causes’. But ‘cause’ isn’t quite right: ‘four questions’ or ‘four kinds of causal explanation’ capture his meaning better: There are four basic causal explanations: first, what something is for (i.e. what its goal is); second, the formal cause or ‘definition of the essence’ (these first two should be treated as pretty well the same thing); third, its material basis and, fourth, its efficient cause or origin of movement.