Q. To begin with, could you describe this work?
A. Yes, of course. What I've done is change a glass of water into a full-grown oak tree without altering the accidents of the glass of water.
Q. The accidents?
A. Yes. The colour, feel, weight, size ...
Q. Do you mean that the glass of water is a symbol of an oak tree?
A. No. It's not a symbol. I've changed the physical substance of the glass of water into that of an oak tree.
Q. It looks like a glass of water.
A. Of course it does. I didn't change its appearance. But it's not a glass of water, it's an oak tree.
Q. Can you prove what you've claimed to have done?
A. Well, yes and no. I claim to have maintained the physical form of the glass of water and, as you can see, I have. However, as one normally looks for evidence of physical change in terms of altered form, no such proof exists.
Q. Haven't you simply called this glass of water an oak tree?
A. Absolutely not. It is not a glass of water anymore. I have changed its actual substance. It would no longer be accurate to call it a glass of water. One could call it anything one wished but that would not alter the fact that it is an oak tree.