Andrzej Sapkowski

‘Evil is evil, Stregobor,’ said the witcher seriously as he got up. ‘Lesser, greater, middling, it’s all the same. Proportions are negotiated, boundaries blurred. I’m not a pious hermit, I haven’t done only good in my life. But if I’m to choose between one evil and another, then I prefer not to choose at all. Time for me to go. We’ll see each other tomorrow

The difference, my dear witcher, is that one who is bought is paid according to the buyer's whim, whereas one who renders a service sets his own price. Is that clear?”