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.

I suppose I've been interested in Abraham Lincoln for almost as long as I can remember. My first Lincoln book was the Classics Illustrated comic book version of the life of Lincoln, and with that, I was hooked.

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.

Until the early 90s, when I was working on a project about the idea of free will in American philosophy. I knew that Lincoln had had something to say about "necessity" and "fatalism," and so I began writing him into the book. In fact, Lincoln took over. I wrote instead 'Abraham Lincoln: Redeemer President,' in 1999, and I've splitting rails with Mr. Lincoln ever since. If there's a twelve-step process for this somewhere, I haven't found it yet.

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.

No one loves an archive better than I do. I can smell a good one half-a-block away - all that brittle papyrus dust is music to my nostrils.

Modern presidential debating only started with Richard Nixon and John F.Kennedy in 1960, although the proximity of that to the Lincoln-Douglas centennial is more than accidental. The reason is, I think, the medium. Abraham Lincoln and Stephen A. Douglas were talking, but the talking was in terms of logic, development, and reasoning. Television, as a medium, resists those qualities in speaking - it favors quick cuts, one-liners, and talking points. I think the modern debates are largely the prisoners of the televised medium