It began with genuine curiosity. Believing that he himself was one of the last people to lead a real political revolution, Gingrich wanted to know how Trump was pulling off what most had written off as an impossible feat, one person close to the former Speaker said.

Known to friends as an insatiable reader with the intellectual appetite of a full-time historian, Gingrich pored through “Trump: The Art of the Deal,” the 1980s autobiography that details Trump’s lessons in business and real estate. Gingrich also read “Trump: The Art of the Comeback,” another autobiography released in the late 1990s after Trump’s companies had gone through bankruptcies.

From these books, Gingrich came to this conclusion: Trump is a practical man who loves to win.

Gingrich was so fascinated by the window he believed these books offered into Trump’s worldview that he would often discuss the writings in public and even encourage political reporters to read them.

In an early January phone interview, Gingrich began the conversation with this advice for a CNN reporter: “First, let me suggest if you haven’t done it, that you ought to read ‘The Art of the Deal,'” Gingrich said. “Because it’s remarkably revealing about Trump’s style and behavior and the way he thinks.”