If you want to learn something for the long run, you have to write it down. If you want to really understand something, you have to translate it into your own words. Thinking takes place as much on paper as in your own head. “Notes on paper, or on a computer screen [...] do not make contemporary physics or other kinds of intellectual endeavour easier, they make it possible,” neuroscientist Neil Levy concludes in the introduction to the Oxford Handbook of Neuroethics, summarizing decades of research.