"Believe" means you are willing to consider some results as premises for your next deduction.
Seriously, philosophy is a personal endeavor. You derive your own, make your own deductions, and you believe in them. That makes it valid for you.
But ... if your philosophy is about how the world works, about some aspects of reality, and you want to ensure that both your philosophy and reality agree, then you can choose to do science:
1. From your philosophy, derive some hypothesis.
2. Check you hypothesis with some experiment.
More important, following this thread upward we see:
1. The urge of some scientists to offer science as a replacement for philosophy was scored as a fatal flaw
2. The question was asked, "Why is this a fatal flaw?"
3. That question was answered with the claim that something called "epistemology" is needed in order to make decisions based on experiences. Evidently, "epistemology" is an essential ingredient to human decisions which would be lost if we tried to replace philosophy with science.
4. But I said, no, I personally don't need "epistemology"--whatever that is--to make decisions.
5. Then it was claimed that whatever I'm doing to make decisions is inherently "philosophy." Yet, I'm not doing anything special, so if I'm doing philosophy then I guess everyone is doing philosophy, even scientists.
6. If that's true then what happened to "epistemology" and the fatal flaw of omitting it in the vain attempt to substitute science for philosophy?
This really isn't adding up.
Professional philosophers do essentially the same thing we do, they derive a set of personal beliefs that they see as trustworthy. The difference is that they go out and try to sell their philosophies to the public as if they were universal, but they aren't, so they almost always fail. Their books and publications tend to be filed under the heading "OPINIONS".
The second topic you mention is about the role of epistemology, in theory the study of knowledge but in practice an amalgam of (once again) opinions from different philosophers. It's difficult to explain epistemology without referring to those opinions, and those may be wrong anyway. Several pieces of the puzzle are still missing.
On the topic of philosophy, if there's two kinds, the kind which comprises opinions sold by professional philosophers to the public as if they're universal but aren't, and the kind which comprises the activities we all do in life, then I'm pretty sure the former is the one being held up to scrutiny as Bergson and Canales try to elbow onto the podium alongside science.
On the topic of epistemology, I don't know a thing about it and I don't think I need to in order to believe the results of experiments or go about life, which pretty much is what also was claimed further up the thread.