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This is backwards: This comment (and its grandparent) makes it sound as though Knuth set out to create a typesetting system and a font creation system, and then was faced with the choice of who would design the first font for the system. In reality, his work in typesetting started with a very narrow goal: when the publishers of TAOCP were about to set the second edition of Volume 2 using phototypesetting (instead of hot-metal typesetting as in the first edition of Vols 1–3 and 2nd edition of Vol 1), he found the galley proofs awful, and at the same time he came to know of the existence of a digital typesetter, so he thought he might be able to retain the appearance of the first edition. That's all there was to it; it was supposed to be a three-month one-off job specifically for TAOCP (and later volumes/editions thereof), and he even thought his grad students could code up the whole thing over the summer while he was away. More concretely: the design of Computer Modern is based on the typeface used for the first edition (10-point Monotype Modern 8A, etc). It's not identical, but you can compare say, the first (1973, Monotype hot metal) and second (1998, using CM/Metafont) editions of Volume 3; it's substantially the same typeface; at least most people's criticisms of Computer Modern would also apply to the font he found so beautiful and which he was trying to reproduce. (Except the "spindly" or "too light" complaint which is not a problem with "true" CM but only with the TrueT