Faith

[Cavernio]

eternity's definition of faith is what rushy used as faith. However, that said, eternity also said: "However, if you decide to do a little research and evaluate the evidence firsthand, then your belief is not faith-based", which, if taken as far as things can possibly go, means that belief the world exists outside our own minds is a part of faith.
I mean, most research people do doesn't involve collecting the data yourself, so you have to trust that whatever you see from somewhere else is accurate. More about this later.