If you want to get rich from writing, write the sort of thing that's read by persons who move their lips when they're reading to themselves.

If you make people think they're thinking, they'll love you; But if you really make them think, they'll hate you.

In order to influence a child, one must be careful not to be that child's parent or grandparent.

If a child shows himself to be incorrigible, he should be decently and quietly beheaded at the age of twelve, lest he grow to maturity marry, and perpetuate hi…

Of all the needs a book has, the chief need is that it be readable.

I guess I think I'm writing for people who are smarter than I am, because then I'll be doing something that's worth their time. I'd be very afraid to write fro…

Someone told me that each equation I included in the book would halve the sales. I therefore resolved not to have any equations at all. In the end, however, I …