I've told the tale before, but am happy to do so again: At work I used to be known generally as a pessimist. Then I changed offices (same company) and instantly was regarded as an optimist. This confused me so I looked both terms up and didn't feel either of the definitions applied to me! I now see myself as a "Pragmatic Murphyist" - I believe that anything that can go wrong will go wrong but, knowing that, am able to prepare for the worst (and am pleasantly surprised whenever it doesn't happen!).