In his 1974 commencement speech at the California Institute of Technology, Nobel laureate physicist Richard P. Feynman articulated the foundation of scientific integrity: “The first principle is that you must not fool yourself—and you are the easiest person to fool.... After you’ve not fooled yourself, it’s easy not to fool other scientists. You just have to be honest in a conventional way after that.”

Unfortunately, says Feynman’s Caltech colleague David Goodstein in his new book On Fact and Fraud: Cautionary Tales from the Front Lines of Science (Princeton University Press, 2010), some scientists do try to fool their colleagues, and believing that everyone is conventionally honest may make a person more likely to be duped by deliberate fraud. Nature may be subtle, but she does not intentionally lie. People do. Why some scientists lie is what Goodstein wants to understand. He begins by debunking myths about science such as: “A scientist should never be motivated to do science for personal gain, advancement or other rewards.” “Scientists should always be objective and impartial when gathering data.” “Scientists must never believe dogmatically in an idea or use rhetorical exaggeration in promoting it.” “Scientists should never permit their judgments to be affected by authority.” These and many other maxims just do not reflect how science works in practice.

Knowing that scientists are highly motivated by status and rewards, that they are no more objective than professionals in other fields, that they can dogmatically defend an idea no less vehemently than ideologues and that they can fall sway to the pull of authority allows us to understand that, in Goodstein’s assessment, “injecting falsehoods into the body of science is rarely, if ever, the purpose of those who perpetrate fraud. They almost always believe that they are injecting a truth into the scientific record.” Goodstein should know because his job as the vice provost of Caltech was to investigate allegations of scientific misconduct. From his investigations Goodstein found three risk factors present in nearly all cases of scientific fraud. The perpetrators, he writes, “1. Were under career pressure; 2. Knew, or thought they knew, what the answer to the problem they were considering would turn out to be if they went to all the trouble of doing the work properly; and 3. Were working in a field where individual experiments are not expected to be precisely reproducible.”

To detect fraud, we must first define it, and Goodstein does: “Research misconduct is defined as fabrication, falsification, or plagiarism in proposing, performing, or reviewing research, or in reporting research results.” Next there must “be significant departure from accepted practices of the scientific community.” Then, the misconduct must be “committed intentionally, or knowingly, or in reckless disregard of accepted practices,” and finally, as in any court of law, the fraud charge must be proved by a preponderance of evidence.

Clear-cut cases of fraud include the twin studies of British psychologist Cyril L. Burt (who faked so many twins that he had to fabricate additional twin researchers), the Sloan-Kettering Institute cancer researcher William Summerlin’s experiments on inducing healthy black skin grafts on white mice (which he was caught enhancing with a black felt-tipped pen), physicist Victor Ninov’s alleged discovery of element 118 (predicted by others so he faked data for its existence), and of course the famous Piltdown Man hoax (which turned out to be the jaw of an orangutan dyed to look old). Other cases are not so clear. Martin Fleischmann and Stanley Pons’s “discovery” of cold fusion, Goodstein concludes, was most likely a case of scientists who “convince themselves that they are in the possession of knowledge that does not in fact exist.” This self-deception is distinctly different from deliberate deception.

So some scientists sin, it’s true. Given the fiercely competitive nature of research funding and the hardscrabble intensity of scientific status seeking, it is surprising that fraud isn’t more rampant. The reason that it is so rare (compared with, say, corruption in politics) is that science is designed to detect deception (of one’s self and others) through colleague collaboration, graduate student mentoring, peer review, experimental corroboration and results replication. The general environment of openness and honesty, though mythic in its idealized form, nonetheless exists and in the long run weeds out the cheats and exposes frauds and hoaxes, as history has demonstrated.