 Plantinga offers a different kind of argument. According to Cartesian-style foundationalism, in order to count as justified, a belief must either be grounded in other justified beliefs, or derive its justification from some special status, like infallibility, incorrigibility, or indubitability. There is a parallel view about knowledge. Plantinga (1981) argued that such a foundationalism is inconsistent with holding one’s own ordinary beliefs about the world to be justified (or knowledge), because our ordinary beliefs derived from sense-experience aren’t derived from anything infallible, indubitable, or incorrigible. In fact, we typically treat them as foundational, in need of no further justification. If we hold sensory beliefs to be properly basic, then we have to hold similarly formed religious beliefs, formed on experiences of God manifesting himself to a believer (Plantinga calls them ‘M-beliefs’), as properly basic. He proposed that human beings have a faculty—what John Calvin called the ‘sensus divinitatis’—that allows them to be aware of God’s actions or dispositions with respect to them. If beliefs formed by sense-experience can be properly basic, then beliefs formed by this faculty cannot, in any principled way, be denied that same status. His developed theory of warrant (2000) implies that, if the beliefs are true, then they are warranted. One cannot attack claims of religious experience without first addressing the question as to whether the religious claims are true. He admits that, since there are people in other religious traditions who have based beliefs about religious matters on similar purported manifestations, they may be able to make the same argument about their own religious experiences.