Kazimierz Bein
Kazimierz Bein (1872 – 15 June 1959), often referred to by his pseudonym Kabe, was a Polish ophthalmologist, the founder and sometime director of the Warsaw Ophthalmic Institute (Warszawski Instytut Oftalmiczny). He was also, for a time, a prominent Esperanto author, translator and activist, until in 1911 he suddenly, without explanation, abandoned the Esperanto movement.