Objection to Foundationalism: The Choice of Basic Beliefs is Arbitrary
According to foundationalism, there are some beliefs that do not need external justification. These beliefs are justified, even without any further reason for believing that they are true.
But who decides which beliefs are to be taken as basic and which are not?
Alvin Plantinga, a Christian philosopher, has suggested that belief in God is basic, denying that there is a need for rational argument to justify religious belief. Astrologists could claim that bleief in astrology is basic, justified without further argument.
The choice of basic beliefs is entirely arbitrary, but directly impacts which of our other beliefs are justified. As the foundation of our belief sets is arbitrary, though, then so must be whole structure of our beliefs; foundationalist justification is therefore worthless.