We’re going to soon be getting into a really fascinating discussion in my Metaphysics and Epistemology course having to do with material object metaphysics. One fascinating case raises a host of philosophical issues. The “statue and clay” example has been discussed for centuries. Here’s how Carroll and Markosian spell it out in their book An Introduction to Metaphysics.
“Suppose that on Monday you bring home a lump of clay and place it on your workbench. Then on Tuesday morning you carefully fashion the clay into a beautiful statue of a snowy owl, which remains in your workshop for all your friends to admire... But suppose that on Wednesday you wake up in a bad mood and decide that you don’t like the snowy owl after all. So that morning you squash it back into an amorphous lump of clay”
How many objects are there on your workbench on Monday, Tuesday, and Wednesday? Does the number change over these days? In other words, are the clay and the owl the same thing or are they, alternatively, two distinct objects?
Ted Sider puts one of the problems raised by this case as follows. (This might as well be this week’s paradox. Please suggest a solution to this.)
(1) Before the sculptor's action, a lump of clay exists and after the sculptor's action a statue exists.
(2) The lump of clay continues to exist after the sculptor's actions.
(3) The statue comes into existence when the sculptor makes it.
(4) The lump of clay and the sculpture have different properties after the sculptor's actions: one existed before the sculptor's action, and one did not. (This follows from (1), (2), and (3).)
(5) If x and y have different properties at the same time, then x ≠ y. (This is called Leibniz’s Law - see here for a robust discussion of this principle.)
(6) The statue ≠ the lump of clay. (This follows from (4) and (5).)
(7) The statue and the lump of clay occupy the same location at the same time.
(8) Two distinct objects never occupy the same location at the same time.
(9) The statue = the clay. (This follows from (7) and (8).)
(10) Therefore, The statue = the clay and the statue ≠ the lump of clay. (This follows from (6) and (9).)Of course, the statue can't be identical to the clay and also not identical to the clay. So what went wrong? Which premise(s) of the argument should we reject?