In Flying Saucers & Science, Stanton Friedman is out to tell us what we don't know about UFOs. Friedman, who has been researching the field for more than 40 years, knows his stuff and doesn't waste readers' time telling them what they already know. He assumes a foreknowledge of the UFO field and spend most of the book refuting the claims of skeptics. He is nothing if not convincing.

If you don't think there is anything to the flying saucer sightings, you'll probably change your mind after reading Friedman. He begins with the statements that skeptics always make:

One: We have only anecdotes about saucer sightings, usually from uneducated people seeking publicity.

Two: No scientists have seen UFOs and there are no radar sightings.

Three: There is no physical evidence.

Four: Governments can't keep secrets.

Five: The crash at Roswell was an array of Mogul balloons.

Then he demonstrates that the thing all these statements have in common is that they are false.

Before taking on science, Friedman points out that what we consider to be the cornerstone of the scientific method, the replication of controlled experiments, is just one type of scientific approach. There are actually several ways to approach science; we can measure the effects of earthquakes, for example, but we cannot accurately predict or control them. We also have the science of the completely unexpected -- airplane crashes, murders, automobile accidents. For those, we rely on the testimony of witnesses.

Using these approaches to science, Friedman tries to establish that UFOs are extraterrestrial and that, despite the claims of skeptical scientists, interplanetary travel is possible. He demonstrates that what he calls a "cosmic Watergate" exists, that evidence of UFOs, including crashes and clashes between Air Force planes and flying saucers have happened -- at least eight American planes have been downed by UFOs, he says -- and are being covered up by our government. (For those who claim governments can't keep secrets, he demonstrates conclusively that they can and do.)

Friedman's is a valuable book, a reasoned and calm discussion by a strong advocate, that is marred only by the fact that the author is not what you might think of as a graceful writer; his prose is stumbling and repetitive. The book needed a good editing job. Still, it constitutes essential reading.