A faulty brain might not be able to determine if it is faulty. Thinking with the same ideas that brought us to the problem won’t solve it.
The most basic idea is unbelief, not belief in nothing, but absence of certainty.
The level playing field is not the assumption that everything is as it appears. If faith is evidence that convinces, then the assumption that everything is as it appears can require faith.
It doesn’t take faith to assume “I don’t know”.