The Word of the Day comes from "ANIMAL" by Lisa Taddeo.
noun noun: solipsism
the view or theory that the self is all that can be known to exist.
the quality of being self-centred or selfish
Solipsism is the philosophical idea that only one's mind is sure to exist. As an epistemological position, solipsism holds that knowledge of anything outside one's own mind is unsure; the external world and other minds cannot be known and might not exist outside the mind.
late 19th century: from Latin solus ‘alone’ + ipse ‘self’ + -ism.
Therefore for anybody reading this there is absolutely no proof that you exist outside my own mind.