There is Bertrand Russell, a logician, who had another career as a philosopher as well as an anti-war protestor. He helped publicise what was happening in Vietnam - in fact, according to Paul McCartney of the Beatles, at one point he lived on the same square or street with Russell and he had knocked on his door to introduce himself and Russell proceeded to tell him all about the war. This is, according to Paul McCartney, how the Beatles became involved in the anti-war protest movement, in particularly against the war of aggression by the USA on Vietnam.

Laurent Schwartz, a french mathematician known for his work was on distributions, was also an anti-war activist and who focused on labour activism as well on the colonial war in Algeria.

Grothendieck, who needs no introduction, was also an ati-war activist, focusing on what was then occuring Vietnam. His fater was a revolutionary socialist. 

Smale was also another anti-war activist; also Solznetseyn and many others.
  

Sofia Kovalevskaya was one of the first handful of female mathematicians. She was also a writer, having written a well-received autobiography, *A Russian Childhood* in where she reveals she met Dostoyevsky as a young woman and did not think much of him. 

Likewise, Lewis Carroll, also a logician and who wrote the best-selling *Alice's Adventures in Wonderland*.

And a special mention for Walter Sisulu, who studied a science degree, but after joining the ANC, was imprisoned several times, and was finally imprisoned on Robbens Island with Nelson Mandela and sentenced to twenty-five years - the same sentence as Nelson. He rose to become the ANC's Secretary-General and Deputy President of the organisation.