"Desire to know why, and how, curiosity; such as is in no living creature but man: so that man is distinguished, not only by his reason, but also by this singular passion from other animals; in whom the appetite of food, and other pleasures of sense, by predominance, take away the care of knowing causes; which is a lust of the mind, that by a perseverance of delight in the continual and indefatigable generation of knowledge, exceedeth the short vehemence of any carnal pleasure."
From which comes the (historic) Wikipedia slogan. Found, via a rather strange route from Jeff Atwood's recent piece on ASCII armor and ASCII85. Jeff points out that you can represent a GUID in 20 printable ASCII characters using ASCII85.