Social media is ephemeral; mathematics has a surprising permanence. Where does that leave mathematics blogs?
Looking at the viewing statistics, it is clear that some of my posts really are ephemeral: a post on my summer holiday has had just seventeen views, despite what I think are nice pictures of a navigating spider, dragon about to fly, and impressive ram. At the other end, the most popular post (by a short head) just happened to catch a wave of publicity at a particular time, but the second most popular, which is usually in the “top ten”, concerns using non-standard LaTeX fonts in Beamer slides, something which very much concerns practising mathematicians.
In the comments to the post, I promised to find Donald Knuth’s comments from The TeXbook about traditional typesetting. Here they are. I enjoy this passage, and I hope you will too.
The principal difference between TeX’s method and the old way is that metal types are generally cast so that each character has the same height and depth; this makes it easy to line them up by hand. TeX’s types have variable height and depth, because the computer has no trouble lining characters up by their baselines, and because the extra information about height and depth helps in the positioning of accents and mathematical symbols.
Another important difference between TeX setting and hand setting is, of course, that TeX will choose line divisions automatically; you don’t have to insert \hbox and \vbox instructions unless you want to retain complete control over where each letter goes. On the other hand, if you do use \hbox and \vbox, you can make TeX do almost everything that Ben Franklin could do in his printer’s shop. You’re only giving up the ability to make the letters come out charmingly crooked or badly inked; for such effects you need to make a new font. (And of course you lose the tactile and olfactory sensations, and the thrill of doing everything by yourself. TeX will never completely replace the good old ways.)