> abstract/concrete ideas If by "idea" you mean "concept", then they can only be abstract. Images are of concrete things. "and when you speak of the 'time-kee

> abstract/concrete ideas If by "idea" you mean "concept", then they can only be abstract. Images are of concrete things. "and when you speak of the 'time-keeping function' of the clock, or of its spring's 'elasticity', it is hard to see exactly what your ideas can copy" This sounds very imagist and Humean. Take any principle or any concept. Can you see the law of contradiction? The primality of numbers? That the sum of the angles of all triangles is 180 degrees? What about your concept of triangle? No, not the image in your mind right now. That's just one particular triangle with definite color and shape. I mean the concept of triangularity, that which is true of all triangles and that which makes the aforementioned law of triangles true. You can't imagine that either. Indeed, this is the basis for the Aristotelian proof of the immateriality of the intellect. If all material things are concrete (this or that triangle), and all concepts are universal (they apply to multiple things but do not exist on their own as such), then the intellect is not material. For if it was material, then it could not "contain" abstract concepts, only concrete images of particular triangles.