We are all aware that the senses can be deceived, the eyes fooled. But how can we be sure our senses are not being deceived at any particular time, or even all the time? Might I just be a brain in a tank somewhere, tricked all my life into believing in the events of this world by some insane computer? And does my life gain or lose meaning based on my reaction to such solipsism?

--- Project PYRRHO, Specimen 46, Vat 7. Activity recorded M.Y. 2302.22467. (TERMINATION OF SPECIMEN ADVISED)

From Sid Meier's Alpha Centauri