Bob Harper's Course on Principles of Programming Languages

He gives a first-hand account of how Per Martin-Löf's 1976 Constructive Mathematics and Computer Programming was received. Partly answers Emily Riehl's question about the schism between type theory and set theory. See About Logic Interview with Emily Riehl. 

30:43 Why Girard called it System F. See System Fω and Total Functional Programming and System Fω And ML Module Semantics. See also Lambda Calculus to System-F.

1:17:59 By way of motivating a study of Plotkin's PCF: for all practical purposes, most total functions are no more informative than partial functions. See Blum's Speedup Theorem. Moral "Most total functions are not interesting!" 

57:58 One way to look at call by name and call by value as types. The earlier comment he refers to for the context (which is partial computable functions) is at 40:00. See also Paul Levy - What Is a Monoid? and Mike Stay's remarks in Frank Pfenning's Course on Linear Logic.

Part 3 is on recursive types, for the first bit, then a rant about scheme! See How Could One Unify CMU and MIT.

8:24 Scott topology and recursive types modelled as partial functions.

The full series of lectures is in a YouTube playlist. 

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