My friend James Randi speculates--with only partial facetiousness--that when one receives a Ph.D., a chemical secreted from the diploma parchment enters the brain and prevents the recipient from ever again saying "I don't know" and "I was wrong." As one counterexample I hereby confess that in my column on Chinese science in the July issue I was wrong in my conversion of Chinese yuan as 80 to the dollar (it is eight).
More serious was a statement I made in the June issue about a Fox television program claiming that the moon landing was faked. I said that the lunar lander rocket showed no exhaust because there is no oxygen-rich atmosphere on the moon. I was partially wrong. The lack of an atmosphere plays a minor role; the main reason is that the lander's engine used hypergolic propellants that burn very cleanly. In both instances, readers were kind enough to provide constructive criticism.
This article was originally published with the title I Was Wrong.