The best one-volume biography of Abraham Lincoln is still Benjamin Thomas's 1952 biography. David Donald's 1995 biography is a close second, and close enough that if you can only obtain the Donald rather than the Thomas, your book club will still be doing just fine.

We still know so little about how the brain interacts with the body chemistry or, for that matter, whether we should be talking about the brain or the mind, that it would be perilous to hazard any guess about the way Abraham Lincoln's biological health may or may not have affected him. Of course, we don't have Lincoln on hand to ask him directly; but even if we did, we still might not be able to make sense of how all the parts worked together.

When I need to stretch my legs, I can walk across the street to the museum and relax among the illustrations of Abraham Lincoln's life, too. In a way, it reflects the halves of Lincoln's own character - one all jokes and buffoonery, the other all high-minded seriousness. If he could absorb both into his personality, I think I can, too.

I suspect, too, that the modern debates represent the effort of candidates with widely-varying constituencies and special interests to please to tip the hat as quickly as possible to as many of the constituencies and interests as possible. That leaves no time for big-picture issues. Contrast this with Abraham Lincoln and Stephen A. Douglas, where the subject was only ever slavery, and the discussion went right to the bedrock of what a democracy is all about.

I don't know that there has ever been a time when Abraham Lincoln didn't stand head-and-shoulders above all other presidents in the historians' eye. But relatively speaking, there have been peaks and a troughs. One peak was in the 1910s-20s; a major trough was in the 1970s-80s. We are certainly on a peak again, something which began in 1994 with Michael Burlingame's 'The Inner World of Abraham Lincoln,' which showed in fabulous detail how many new and untapped sources were available on Lincoln.

The one who pursues revenge should dig two graves.

It's often said that leadership is the art of getting people to do what you want, and making them think it's what they want. This captures a lot of what Abraham Lincoln did.