By His Bootstraps

Concerning the man who not only met himsetf, but stood by while hisself fought himself!
Bob Wilson did not see the circle grow.
Nor, for that matter, did he see the stranger who stepped out of the circle and stood staring at the back of Wilson's neck-stared, and breathed heavily, as if laboring under strong and unusual emotion.
Wilson had no reason to suspect that anyone else was in his room; he had every reason to expect the contrary. He had locked himself in his room for the purpose of completing his thesis in one sustained drive. He had to―tomorrow was the last day for submission, yesterday the thesis had been no more than a title: An Investigation Into Certain Mathematical Aspects of a Rigor of Metaphysics.
Fifty-two cigarettes, four pots of coffee and thirteen hours of continuous work had added seven thousand words to the title. As to the validity of his thesis he was far too groggy to give a damn. Get it done, was his only thought, get it done, turn it in, take three stiff drinks and sleep for a week.
He glanced up and let his eyes rest on his wardrobe door, behind which he had cached a gin bottle, nearly full. No, he admonished himself, one more drink and you'll never finish it, Bob, old son.
The stranger behind him said nothing.
Wilson resumed typing. ―nor is it valid to assume that a conceivable proposition is necessarily a possible proposition, even when it is possible to formulate mathematics which describes the proposition with exactness. A case in point is the concept 'time travel.' Time travel may be imagined and its necessities may be formulated under any and all theories of time, formulae which resolve the paradoxes of each theory. Nevertheless, we know certain things about the empirical nature of time which preclude the possibility of the conceivable proposition. Duration is an attribute of consciousness and not of the plenum. It has no Ding an Sich. Therefore―
A key of the typewriter stuck, three more jammed up on top of it. Wilson swore dully and reached forward to straighten out the cantankerous machinery. Don't bother with it, he heard a voice say. It's a lot of utter hogwash anyhow.