I am not a manual labourer and please God I never shall be one, but there are some kinds of manual work that I could do if I had to. At a pitch I could be a tolerable road-sweeper or an inefficient gardener or even a tenth-rate farm hand. But by no conceivable amount of effort or training could I become a coal-miner; the work would kill me in a few weeks.
– George Orwell, The Road to Wigan Pier, (Harcourt 1958), pg. 32