In the beginning of 1977 I spent the first 3 months writing part of Volume Four.  I… I, you know, I had completed all my reading for Volume Four and I was ready to come… to… to finally type some pages.  And I typed up a hundred and some pages.  But the meanwhile that was the… that overlap with the period when I had discovered about digital typography, that… that you could get good quality from computer output. And so, my plan had been to go to Chile and spend a year working on Volume Four – my… my first real sabbatical – and I cancelled that to stay… to stay at Stanford and I… and I stopped working on Volume Four, put that on hold starting in April of '77 and began to say, well, let me spend a year writing computer programs that will make my book look okay again.
 
And so, first I… first I thought… I had seen some people at Xerox Palo Alto Research Center playing with letter forms – Butler Lampson especially, I remember sitting… sitting in front of a computer monitor and he had a big capital B on the screen and he was looking at spline curves along the edge that would… that would trace the edges of the B, and I… I thought, okay, that would be pretty easy, I'll… I'll just capture all of the letter forms from my book, I'll go over to Xerox and use their equipment and… and I'll write a program that… that reproduces the format of The Art of Computer Programming, and I have a year to kill, so I'll do this. Well, the first thing that went wrong was Xerox said, ‘Oh yes, it will be fine if you come over and use our equipment, but then we own all of the fonts that you produce’.  And I said, ‘No, no, I wanted these, you know, this is mathematics that… all that’s going to come out of here… here is a bunch of numbers that say… that say where… where the edges of these letters are, but these are… these just numbers. How can you own these numbers? You know, the numbers belong to the world.’
 
But so I, anyway, I decided I… I would work at Stanford instead. Stanford didn't have very good equipment. The… we had some old TV cameras, and if you changed the lighting by a little bit in the room, the letters would get 50% darker. So, you… there was absolutely no way to get consistency between one day's work and another day's work, and consistency is… is really important for… to get good looking letters.