He’s talking about the Lewis Carroll dialog that inspired the ones in GEB. “What the tortoise said to Achilles.”
The point of the dialog is that there’s something irreducibly ‘dynamic’ about the process of logical inference. Believing “A” and “A implies B” does not compel you to believe “B”. Even if you also believe “A and (A implies B) together imply B”. A static ‘picture’ of an inference is not itself an inference.
He’s talking about the Lewis Carroll dialog that inspired the ones in GEB. “What the tortoise said to Achilles.”
The point of the dialog is that there’s something irreducibly ‘dynamic’ about the process of logical inference. Believing “A” and “A implies B” does not compel you to believe “B”. Even if you also believe “A and (A implies B) together imply B”. A static ‘picture’ of an inference is not itself an inference.
There was supposed to be a link there but I accidentally deleted it. It’s fixed.