Hugh Pickens writes writes: "Biologist David P. Barash writes in the LA Times that as a scientist he has been participating in a deception for more than four decades — a benevolent and well intentioned deception — but a deception nonetheless. "When scientists speak to the public or to students, we talk about what we know, what science has discovered," writes Barash. "After all, we work hard deciphering nature's secrets and we're proud whenever we succeed. But it gives the false impression that we know pretty much everything, whereas the reality is that there's a whole lot more that we don't know." Teaching and writing only about what is known risks turning science into a mere catalog of established facts, suggesting that "knowing" science is a matter of memorizing says Barash. "It is time, therefore, to start teaching courses, giving lectures and writing books about what we don't know about biology, chemistry, geology, physics, mathematics." Barash isn't talking about the obvious unknowns, such as "Is there life on other planets?" Looking just at his field, evolutionary biology, the unknowns are immense: How widespread are nonadaptive traits? To what extent does evolution proceed by very small, gradual steps versus larger, quantum jumps? What is the purpose of all that "junk DNA"? Did human beings evolve from a single lineage, or many times, independently? Why does homosexuality persist? According to Barash scientists need to keep celebrating and transmitting what they know but also need to keep their eyes on what science doesn't know if the scientific enterprise is to continue attracting new adherents who will keep pushing the envelope of our knowledge rather than resting satisfied within its cozy boundaries. As Richard Dawkins writes: "Mystics exult in mystery and want it to stay mysterious. Scientists exult in mystery for a different reason: It gives them something to do.""