The Wordnik Word of the Day for November 8, 2011 is meliorism wordnik.com
(noun) A pit-like structure created by an impacting meteorite.
(noun) The improvement of society by regulated practical means: opposed to the passive principle of both pessimism and optimism.
(noun) The doctrine that the world is neither the worst nor the best possible, but that it is capable of improvement: a mean between theoretical pessimism and optimism.
Example:
"The term optimism as thus extended would also include 'meliorism', a word first used in print by Sully to designate the theory of those who hold that things are, indeed, bad, but that they can be better, and that it is in our power to increase the happiness and welfare of mankind."
--The Catholic Encyclopedia, Volume 11: New Mexico-Philip