For Galen, the purpose of the divine Craftsman is, certainly, the most important cause, but the material cause must also be mentioned in a full account: matter represents the building-blocks used to realize the design, and in a sense provides a limitation to it. This interaction between design and material—and the assertion of the final cause in opposition to those who deny it—are the central features of Galen’s account. In the (strikingly anthropomorphic) account of the Craftsman’s construction