<p>Jobbin, these people aren’t just people whose parents made them work hard or something, they’re prodigiously crazy. Think about it – to get a PhD in something, you probably have some course requirements and have to pass a qualifying exam or two, and then really all you need to do is do your dissertation. A smart person with something of a decent head start could ver well do the non-dissertation work in a year, though this isn’t a sign of brilliance. However…</p>
<p>Some people are abnormally crazy; they were just beasts and probably didn’t just learn the material out of pushing themselves, but are the types of people who can read absurdly difficult books and master them in a small fraction of the time it would take someone like me, or even someone much brighter than I am. They may have solved something as a high schooler that could be the dissertation of topic of someone doing a PhD at MIT, i.e. something which takes absurd background, creativity, etc. </p>
<p>Classes are very easy once you know volumes beyond what is done in them.</p>