Belief systems are good to have. Philosophy is another belief system. It is a liberal arts, not a science, because it's basis requires belief.

Science can tell us why someone died, when, if it was a murder, etc. It doesn't tell us why murder us wrong - at best it tells us logical reasons why we wouldn't want to murder someone in a situation due to our own benefits, but not why it's wrong.

For that we have ethics and morality, which are based in beliefs. Religion is one basis for these beliefs, but isn't in any way necessary. One canuse traditional and modern philosophical study and arguments to form an extremely sound belief system.

Ultimately, it's what you choose to follow that defines those beliefs. There is true to the idea that even the most devote are appealing to their own personal beliefs in many matters - even if they don't realize, or chose to ignore, that their beliefs differ from popular doctrine.

Just like every philosophical stance, every religion is open to interpretation, so no two people are exactly following the same thing. They are all Belief systems, and we depend upon them to make decisions.

I don't view this as an argument for religion; quite the opposite. I think religion as a basis for beliefs often avoids a lot of moral arguments and different views in favor of dictating a belief as you should follow it. Years of study may allow you to ponder meaning and less subjective views, but a background in modern philosophical deduction and reasoning better formalizes and orders the process.