One thing that I find still both fascinating and shocking at the same time is how little we know about learning. If you look at the literature on learning, ther

One thing that I find still both fascinating and shocking at the same time is how little we know about learning. If you look at the literature on learning, there are lots of schools, theories... almost all with only very little empirical work to verify and falsify. Take something relatively simple like learning to read. It's relatively straight forward to test, it's usually learned in relatively tightly controlled environments (schools) and yet we har no idea what is the best way to teach kids how to read. It would be comparitavely easy to conduct large scale experiments: make several groups of schools use different approaches to teach reading over several years, conduct standardised tests and compare. The populations could easily be large enough to average out other variables and after some time we would have a reasonable good idea which approach works and which doesn't. Instead we have a bunch of deductively derived theories paired with small scale qualitative studies ("it worked for me") , with dubious statistical significance. It is quite frustrating really.