Can you give your analysis on the capabilities of the students surrounding Facebook at the time? They were probably all bright and talented, but did they have the drive, dedication, analytical skills, and abilities to do what was required to succeed? I'm curious because Harvard has the best and brighest in the country (arguably), and I'm wondering exactly what that means in a quantifiable way.
The short version of my answer to your question is that you really already answered it--you have to define success first. Mark has succeeded at things I've failed at, and I've succeeded at things that Mark has failed at. Does that make one of us "better" than the other? In monetary terms, maybe eventually, but even those terms haven't been strictly defined yet for the time being. In moral terms, I think there's a clear answer to that question, but it's not going to yield a number for you.
Besides, who says that everything has to be quantifiable? Some things in life just aren't.
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