Ed Witten is the kind of genius other incredibly intelligent theorists and mathematicians will look up to in awe, that's how scarily smart the guy is. He clearly knows his stuff when it comes to QFT, string theory and any related mathematics. As someone taking graduate courses in QFT and general relativity I can appreciate the sheer amount of stuff to learn. My question is how does someone with an undergraduate degree in history who dropped out of one semester in a graduate economics program just enrol in applied mathematics at Princeton before shifting to a physics phd, and somehow manage to assimilate all this information in such a short period? I mean ok he's a genius, but even assuming a perfect information absorption rate of absolutely understanding everything you read immediately, you still have to actually *read* the stuff and that's gigantic books worth of material. And he didn't even do undergrad physics? How did he convince Princeton that he would just pick everything up? Did he learn all this in parallel while studying history and prove to them he was up to standard to just jump into a maths phd? I'm genuinely curious to know what his early learning background is, genius or not everyone has to learn at some stage.