There is a nice 2003 paper by Noson Yanofsky of Brooklyn College on Lawvere’s arguments, available here:

]]>Lawvere’s paper is:

F. W. Lawvere: “Diagonal arguments and cartesian closed categories.”

In: Category Theory, Homology Theory and their Applications, II (Battelle Institute Conference, Seattle, WA, 1968, Vol. Two), pages 134–145.

Springer, Berlin, 1969.