ni·hil·ism
/ˈnīəˌlizəm,ˈnēəˌlizəm/
*noun*
the rejection of all religious and moral principles, in the belief that life is meaningless.
Similar:
negativity, cynicism, pessimism, rejection, repudiation, renunciation, denial, abnegation, disbelief, nonbelief, unbelief, scepticism, lack of conviction, absence of moral values, agnosticism ,atheism , nontheism.
///!PHILOSOPHY!///:
extreme skepticism maintaining that nothing in the world has a real existence.