The thing to keep in mind about Peterson is that he uses religion and philosophy as a basis for everything. That's why it's kind of funny when people shout "He talks about facts" as most of what he talks about is metaphysical and hypothetical. It's pure philosophy rather than science.
But that's what Psychology is to the main part. It's a heavy focus on the metaphysical rather than logical reasoning. Top quote a Yale Psychology professor, "We don't actually know if Psychology actually works because there's no real measurement"