It depends on what supports the solid rock ( foundation) You are not willing to look underneath, but doesn t mean other ppl can t see what s below it. I don t know what to belive, as i m always wrong in what i believe. There could be some evil demon that want to deceive me, to persuad me to believe 2+2=5. So how can be sure of anything, mathemicants. Here s one thing that i can t be wrong about. Suppose the evil genious is trying to convince me of everything , telling me that i exist even though i don t. If i think that i exist, then i t be deceived, then that means i m thinkg of something. Then i m gonna be there to think a thing. Then that s the rock bottom of belief that there s can t be anything more than my own existence.