Or you could argue that philosophy is a subset of Science because Science is about constructing theories and exploring their implications. Science puts a heavy emphasis on reproducible results, while philosophy hasn't generally. Science has methods, one of which is a peer-reviewed publication model that other disciplines have come to adopt, even philosophy? Is Science outside everything then? I don't really think so.

So, I just fundamentally disagree that Philosophy contains everything that has something to do with thinking or believing stuff. It's an oversimplification to the point of being vacuously true.