> We were a bit surprised to hear that he essentially memorized a large part of a table of logarithms. But maybe he was just trolling us. I am not familiar wit

> We were a bit surprised to hear that he essentially memorized a large part of a table of logarithms. But maybe he was just trolling us. I am not familiar with that particular demonstration but having studied similar things, they are all a trade-off between doing computation cleverly in your mind and memorizing information. The more you memorize and the less you have to compute on the fly, increasing speed (step 1 of practicing that type of show is to learn mnemotechnic thoroughly).