proportions, as an aesthetical Idea, can be completely presented in concreto in a model. In order to make intelligible in some measure (for who can extract her whole secret from nature?) how this comes to pass, we shall attempt a psychological explanation.

We must remark that, in a way quite incomprehensible by us, the Imagination can not only recall, on occasion, the signs for concepts long past, but can also reproduce the image of the figure of the object out of an unspeakable number of objects of different kinds or even of the same kind. Further, if the mind is concerned with comparisons, the Imagination can, in all probability, actually though unconsciously let one image glide into another, and thus by the concurrence of several of the same kind come by an average, which serves as the common measure of all.