if there is no way to justify the premise that the world exists without resort to assumptions, then we're no better than the people who believe in God on faith.

Let us imagine two people. One believes "on faith" that (1) what their senses tell them has some correlation with how things really are, (2) their memory has some correlation with the past, and (3) their reasoning isn't completely random and broken. The other believes "on faith" those three things, and also that every statement in a certain collection of ancient documents is true, that a certain person who lived 2000 years ago was really a god in human form, that our true selves are immortal immaterial entities, and that after our deaths we will be judged and consigned to eternal bliss or eternal torment.

I'm quite happy saying that the first of those people is doing better than the second. S/he needs to assume far less; the things s/he assumes are more obviously true and more obviously unavoidable assumptions; there is less arbitrariness to them.

Both of them, indeed, fail if you judge them according to the following principle: "Everything you believe should be derived from absolutely incontestable axioms with which no one could possibly disagree". But why on earth should we do that?