An unimportant little note (but one day I might start collecting these under "things I learned"

[fpb]

If anyone other than a medical doctor, bishop, or minister signs (EDITED IN a book or an article as) "Dr." so and so, you may safely conclude that s/he is a jumped-up ignoramus, and probably a snake oil salesman. Of course, plenty of bishops and ministers - and the odd medical doctor - also qualify, but in their case that is independent of their being called "Dr.".