Alfred Mendelsohn composed in 1972 an opera named aftetr a Dutch philsopher. The philosopher is best knwn for his efforts to apply the strict logic of mathmatics and natural sciences to the feild of sociology, ethics and so on. His masterpiece is entitled "Ethica ordine gerometrica demonstrata" (Ethics shown in a Geometrical Way). Who is this philosopher?
http://www.google.com/search?hl=en&ie=UTF-8&sa=X&oi=spell&resnum=0&ct=result&cd=1&q=+%22Ethica+ordine+geometrico+demonstrata%22+&spell=1
Alfred Mendelsohn died in 1966- are you sure?
The philospher who wrote Ethica ordine geometrica demonstrata (you didn't spell it quite right) was Benedict(us) Spinoza (the Ethica is probably what's best known as his "Ethics" nowadays in translation and can be downloaded in print or free audiobook online...)
Third answer- actually, Alfred Mendelsohn DID in fact write a "Spinoza" opera, in 1966, I see. (Maybe 1972 was a date of posthumous publication or of premiere- these should never be confused with composition date- but they often are, sometimes with very silly results, as when a Bach work published in the 2000s ... well... one sees.)
My bad though- you got it right. Cheers!
(Brief explanation... Alfred Mendelsohn - Romanian composer, 1910-1966, born & died in Bucharest. 8 symphonies (I've heard a broadcast of no.6- neat stuff...)
See Wikipedia for example. :) )
The philosopher you are referring to is Baruch Spinoza, also known as Benedict de Spinoza. He was a 17th-century Dutch philosopher of Portuguese-Jewish origin. Spinoza is famous for his work in various fields, including metaphysics, epistemology, ethics, and political philosophy.
To find the name of the philosopher, you mentioned some key details such as his significant contributions and the title of his masterpiece. By searching for the opera composed by Alfred Mendelsohn in 1972 and its inspiration, you can narrow down the choices and find that Baruch Spinoza is the philosopher associated with the opera.