Percentage margins don't matter. What matters always is dollar margins: the actual dollar amount. Companies are valued not on their percentage margins, but on how many dollars they actually make, and a multiple of that.

Ebooks had to happen.

Our point of view is we will sell more if we help people make purchasing decisions.

Mediocre theoretical physicists make no progress. They spend all their time understanding other people's progress.

I went to Princeton specifically to study physics.

Percentage margins don't matter. What matters always is dollar margins: the actual dollar amount. Companies are valued not on their percentage margins, but on how many dollars they actually make, and a multiple of that.

Am I going to regret leaving Wall Street? No. Will I regret missing the beginning of the Internet? Yes.