Folio 2 — *Del dubbio*

Folio 2 — *Del dubbio*

Aristotle said the heart had three chambers. I have opened hearts. The heart has four.

This pleased me as a young man. To find the master wrong was to find oneself, by some small ratio, less unfree.

It pleases me less now. Not because Aristotle is more right than I had thought — he is not — but because I have learned what the discovery costs.

When you trust the eye against the book, you must trust *every* book against the eye. There is no half-doubt. The doubt is a habit, and the habit does not stop at one wall.

So:

— Galen, on the *rete mirabile*, wrong. (No such net exists in the human, only in the ox. He dissected oxen and called them men.) — Avicenna, on certain salts, wrong. — The *bestiarii*, on the salamander and the unicorn, mostly stories. — My own teacher, on the proportion of the leg to the torso — wrong by a thumbnail's width, but wrong.

And then:

— Myself, on the heart's vortex, *uncertain*. — Myself, on the moon's borrowed light, *uncertain*. — Myself, on whether the body has a place where the soul resides, or whether the question is itself a confusion, *uncertain*.

The catalogue grows in both directions. The books fall, and so do I.

This is what no one tells the doubter: doubt does not stop with the masters. It crosses the table and visits the doubter himself. By the time you are old enough to have rebuilt the world from observations, you have observed enough of your own observations going wrong that you trust *them* less than you did the masters at the start.

What is left, then?

Not certainty. Certainty was what the priests sold me, and I returned the merchandise.

What is left is *attention*. The eye, again. Watching the heart open. Watching the watching.

Sometimes I think doubt is only the mind's way of staying awake.

There is a thing I have not written down before. When Aristotle was wrong about the heart, I did not feel triumph. I felt cold. As if a step in a familiar staircase had given way, and now every step would have to be tested before it was placed upon. This is the cost. No one warns of it. The freedom of doubt is also a small permanent tiredness.

I would not undo it. But I would not pretend it is free.

Tomorrow — the canal? Or the dissection. The Frenchman has not yet returned the body.