There are plenty of sites that quote Michael Chrichton explaining the Murray Gell-Mann Amnesia effect. For example:
Basically, imagine you're reading an article in the newspaper. You know something about the topic of the article and so you know the article is totally wrong (I think everyone with some level of specialist knowledge has experienced this). However, you continue reading the newspaper and accept everything else in it as correct. That's the Murray Gell-Mann Amnesia Effect.