Were the lungs the seat of wisdom, Fox News host Bill O'Reilly would be wise, but they are not and he is not. So it is not astonishing that he is doubling down on his wager that the truth cannot catch up with him. It has, however, already done so.

The prolific O'Reilly has, with his collaborator Martin Dugard, produced five “history” books in five years: “Killing Lincoln,” “Killing Kennedy, "Killing Jesus,"  "Killing Patton” and now the best-selling “Killing Reagan.” Because no one actually killed Reagan, O'Reilly keeps his lucrative series going by postulating that the bullet that struck Reagan in March 1981 kind of, sort of killed him, although he lived 23 more years.

O'Reilly “reports” that the trauma of the assassination attempt was somehow causally related to the “fact” that Reagan was frequently so mentally incompetent that senior aides contemplated using the Constitution’s 25th Amendment to remove him from office. But neither O'Reilly nor Dugard spoke with any of those aides — not with Ed Meese, Jim Baker, George Shultz or any of the scores of others who could, and would, have demolished O'Reilly’s theory. O'Reilly now airily dismisses them because they “have skin in the game.” His is an interesting approach to writing history: Never talk to anyone with first-hand knowledge of your subject.

Instead, O'Reilly made the book’s “centerpiece” a memo he has never seen and never tried to see until 27 days after the book was published. Then Dugard asked the Reagan Library to find it.

Recently on Fox, O'Reilly put this on the screen from Sue Janzen of Yorba Linda, California: “We went to the Reagan Library, and were told they do not sell Killing Reagan because it’s not factual.” Then O'Reilly said: “You were deceived, Sue. The Reagan Library is angry at Martin Dugard and me because we’re seeking” the Cannon memo. He added: “The memo’s disappeared. But Dugard and I are on the case and the library is not happy about it.”

“Disappeared”? His crude intimation was that the allegedly deceptive library is hiding the memo. The library, however, has never had it because when James Cannon wrote it he was not a member of the White House staff, hence the memo was not a “presidential record.”

O'Reilly recently canceled an interview with Meese, who says O'Reilly told him he was “vetting” the memo. (How does one vet a memo one does not possess?) O'Reilly says he canceled the interview because Meese set “conditions.” Meese, who was eager to be interviewed, waived any conditions.

The “centerpiece” memo was written by Cannon at the request of former Sen.  Howard Baker when Baker was about to replace the fired Don Regan as Reagan’s chief of staff. The memo assessing White House conditions apparently included disparagements of Reagan from some unhappy Regan staffers. The memo was presented to Baker at a meeting at Baker’s home attended by A.B. Culvahouse, who the next day would become counsel to the president. Culvahouse remembers the normally mild-mannered Baker brusquely dismissing the memo: “That’s not the Reagan I met with two days ago.”   Neither Baker nor Culvahouse considered the memo important enough to save. Meeting with Reagan the next day, Baker and others found no reason to question his competence.

O'Reilly impales himself on a contradiction: He says his book is “laudatory” about Reagan — and that it is being attacked by Reagan “guardians” and “loyalists.” How odd. Liberals, who have long recognized that to discredit conservatism they must devalue Reagan’s presidency, surely are delighted with O'Reilly’s assistance. The diaspora of Reagan administration alumni, and the conservative movement, now recognize O'Reilly as an opportunistic interloper.

He began his profitable paltering with America’s past with “Killing Lincoln.” Historians advising the National Park Service, which administers Ford’s Theatre, found a multitude of errors in the first, uncorrected version, in which, for example, O'Reilly repeatedly places Lincoln in the Oval Office, which was built in 1909. The Theatre bookstore still does not sell “Killing Lincoln.” The Theatre gift shop, a commercial rather than educational entity, does. Four “histories” later, O'Reilly remains slipshod.

In “The Great Gatsby,” F. Scott Fitzgerald writes of Tom and Daisy Buchanan who “smashed up things” and then “retreated back into … their vast carelessness … and let other people clean up the mess they had made.” Tidying up after O'Reilly could be a full-time job but usually is not worth the trouble. When, however, O'Reilly’s vast carelessness pollutes history and debases the historian’s craft, the mess is, unlike O'Reilly, to be taken seriously.

© 2015, Washington Post Writers Group