Well, I don't want to ruin your enlightenment... but actually Geralt mispronounces Dijkstra. I know, whether you consider the Witcher's World to be Polish or English, it would probably not be pronounced correctly in the universe anyway, but the 'ij' diphthong only occurs in Dutch as far as I know - and is not pronounced 'ee' but ɛɪ̯ (sorry, can't think of the English equivalent at the moment).
Ei as in Eight.
So Daykstra? (ish).