Not everyone in science is a native speaker of English. In many languages it makes no sense to say "can see", seeing implies the ability. Similarly with "can he

Not everyone in science is a native speaker of English. In many languages it makes no sense to say "can see", seeing implies the ability. Similarly with "can hear". In fact, as a Hungarian native speaker it was very weird to me when my English teacher insisted I insert "can"s before hear and see in my writing. What do you mean you "can hear" the loud music coming from the neighbor's flat? Do you in fact hear it or do you just have the ability to hear it and can also switch it off or something? It's a quirk of English that I just had to memorize.