In my continuing tradition of pointing out the problems with cherished cliches, I’d like to address the saying that “nothing’s perfect”.
What is usually meant by ‘perfect’? People often use the phrase to express the idea that no situation is likely to have all of the properties they want, with the missing or undesired properties being considered to be flaws.
Every object or situation has a complete description. If that description is used to define what you’re looking for, that entity fits those criteria perfectly, possessing all listed qualities and having no additional ones. Everything is perfect according to the right set of standards.
The point is that it’s not very useful to conform the standards of your search with what you’re presented with. The purpose of the search is to find something similar to a pre-existing set of standards, a definition that we start out with and don’t vary at will.
This principle is very important when considering Eliezer Yudkowsky’s ‘meta-ethical’ claims.