### VME3?

The Epp text, as I remarked in the previous post, is comfortingly similar in its notations with my own long-dormant lecture notes; I propose to remark for a while on the differences and see what happens.

From the first section, the most striking change is Epp’s introduction of (boldface) symbols t and c for tautology and contradiction (respectively; duh). I’ve always been in the habit of using (“small caps” in MEdZ #1 [The Hip-pocket Vocab]… the glossary for the “lecture notes” I mentioned a moment ago.. but represented here with ordinary capital letters) the symbols T and F (standing for, you guessed, True and False) rather than t and c. I used to read about logic a lot and don’t remember encountering Epp’s notation… but this proves nothing. Maybe there’s some good, though very likely somewhat philosophical, reason for having different symbols for (what amount to) theconstants t and c (say) and the “truth values” T and F. But probably I’ll never guess it; maybe it’s from too much time thinking “1” and “0”.

Anyhow, it’s interesting among other reasons for putting typography right up front (“t” had darn well better be distinguished from “t” in our context since sooner or later somebody’s gonna look at variables p, q, r and so on and need a couple more and make the obvious choices…). Which brings us to handwriting.

I went ahead and introduced the convention that “boldface in the text gets ‘barred’ in handwritten work”; thus $\bar{t} := {\bf t}$. This is very common in courses involving (so-called) vectors, which often appear in contemporary texts as boldface letters and in handwritten work as barred letters. Now to see if anybody picks up on it.