Greenspan’s rise to prominence came entirely from political appointments. He served as chief economist to Gerald Ford from 1974 to 1977. He was appointed Fed chairman by Reagan in 1987 and then reappointed by George H. W. Bush, Bill Clinton and George W. Bush. He kept the job for an astounding 18 years.

It is against this backdrop that Green­span’s new book, “The Map and the Territory,” is best understood. The book offers much wisdom, but that wisdom comes wrapped in a strange package.

First, the wisdom. Because of Green­span’s nontraditional ascent to economic eminence, he sees the world through a different set of eyes than do many others in his field. He is driven less by theory, more by data and practical experience.

In addition, although Greenspan lacks the training that accrues as young economists climb their way up the academic ladder, he had a rare form of education. Being Fed chairman is not only a great responsibility but also a great way to learn. The Federal Reserve’s staff includes hundreds of excellent economists, whose main responsibility is to make sure the chairman (or chairwoman) knows what he (or she) is doing.

Greenspan’s new book lays out his worldview in light of the financial crisis, the deep recession and the meager recovery of the past five years. His critics often condemn him as an ideologue, but the book demonstrates the unfairness of that accusation. On a wide range of topics — from monetary, fiscal and financial policy to productivity, inequality and globalization — he offers readers a thoughtful, nuanced and open-minded perspective, tempered by many years of having seen both business and public policy from the inside.

His comments on financial regulation will garner much attention, for he is frequently blamed for having set the stage for the recent crisis. Greenspan concedes that as Fed chairman, he was too sanguine about the ability of financial institutions to act rationally and prudently. He now gives greater weight to the role of irrational “animal spirits” and advocates much higher capital requirements. Yet he also cautions, correctly in my view, against placing too much faith in the foresight of regulators, who are likely to succumb to whatever irrationality is in vogue. Financial regulators are just as human as those they are regulating, just not as well paid.