"The highest wisdom is not founded on reason alone, nor on the worldly sciences"
Russian philosopher Vladimir Solovyov by Ivan Kramskoi
Public DomainRussian philosopher Vladimir Solovyov by Ivan Kramskoi

 Russian philosophy developed on slightly different lines to that of the rest of Western Europe - although that is not to say that Russian thinkers were not tackling the same issues, and reading the same philosophers, as their Western European counterparts. 

Many Russian philosophers questioned the emphasis on rationalism and scientific knowledge that governed Western European philosophy after the Enlightenment. Partly out of a general suspicion of the West, and partly out of their own culture's emphasis on the idea of the soul and the spirit, Russian philosophy often concluded that pure, cold rationalism denies the importance of these unsayable things.

A good introduction to this subject is Frederick Copleston's Russian Philosophy.