God, in that sense, didn't invent philosophy. In one sense, you are right. Philosophy, like plumbing, is a human invention. But God invented us with the capability to do both. I think he expects us to do both.
Science is philosophy, in a matter of speaking.
In that regard, one person's philosophy is another's junk. This seems to turn on word definitions, more than anything else. We disagree on those definitions. Hence, what I believe comes down to that - faith. And I choose to believe in the Bible.