Note that Principia Mathematica used both "and" and "not" as a complete system. Somehow, Russell and Whitehead missed out on using the Sheffer stroke ("nand") or "nor." Either of these would be more minimal than PM's usage but equally difficult to read. More modern logic books use at least: and, or, not, implies, equivalent, and some add nand and nor.
Note that Principia Mathematica used both "and" and "not" as a complete system. Somehow, Russell and Whitehead missed out on using the Sheffer stroke ("nand") or "nor." Either of these would be more minimal than PM's usage but equally difficult to read. More modern logic books use at least: and, or, not, implies, equivalent, and some add nand and nor.'
Sheffer published his article in 1913, after the first (and, as it turned out, only) three volumes of Principia Mathematica had been published. Somewhere in a box lies my copy of Principia Mathematica to *56, so I can't verify the accuracy of the following statement, but I think it's correct:
This insight [i.e., that propositional logic can be derived using the Sheffer stroke as the sole primitive operation] is discussed in the Introduction to the Second Edition, on pp. xiii to xvi.
BTW, thanks, too, for your post #48.