Let me tell you a fun story. Once upon a time, there were these two religious groups: TEST and HML-ABC. These two groups really got on each others nerves, they frequently battled over which one was the True Way Of The World. TEST would shoot over: "The world was originally intended to look like us". HML-ABC would retort: "you're johnny come lately's, what can you do that we can't?" One day, after much heated battle a member of the HML-ABC screamed: "all TEST objects are 100% isomorphic to HML-ABC objects so laugh it up!"
Then both groups realized something: That guy was right. Then something else slowly dawned on them: isomorphism isn't a one-way street. Just like many religions, most of their differences were really just contrived edge cases. Then they all went home and got some useful work done. Hooray!
# — 02 May, 2003