I agree that there is nothing wrong with believing something without applying critical tests. If something works for you, then feel free to believe in it. If it was called the Principle of Attraction, I would have less of a problem with it. Things become misleading when you have people tell others that they have a one size fits all solution, when what they really are doing is marketing to as many people as possible.

I terms of what science understands, it understands very little. But when something is not completely explainable by science we should make a hypothesis and explore it. What we should not do is begin marketing our solution before we verify it is true. Critical thinking, indeed, must be applied to guide us to the truth.