History of Psychology Timeline:
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A note about dates:  It has become a tradition in the west to use BC (Before Christ) and AD (Anno Domini, "year of our lord," the presumed year of Jesus' birth).  This was started by a monk by the name of Dionysius Exiguus in 525 (AD, of course) while trying to figure out the appropriate dates to celebrate Easter.  As an ancient Roman, he didn't use zero, so the first year was year one, which is the reason that the centuries and the millenia begin a year after they seem like they should (e.g. 2001 instead of 2000).  Because not everyone is Christian (including myself) and because Jesus was probably born several years BC (Before Christ!), many now use the initials BCE (before the common era) and CE (the common era) instead.  Since I am old and cranky, I stubbornly continue to use BC and AD.