 The main argument for foundationalism is called the regress argument. It’s an argument from elimination. With regard to every justified belief, B1, the question arises of where B1’s justification comes from. If B1 is not basic, it would have to come from another belief, B2. But B2 can justify B1 only if B2 is justified itself. If B2 is basic, the justificatory chain would end with B2. But if B2 is not basic, we need a further belief, B3. If B3 is not basic, we need a fourth belief, and so forth. Unless the ensuing regress terminates in a basic belief, we get two possibilities: the regress will either loop back to B1 or continue ad infinitum. According to the regress argument, both of these possibilities are unacceptable. Therefore, if there are justified beliefs, there must be basic  beliefs.[49]