I think one can make a decent philosophical, cumulative case for the existence of God. Not an airtight, open and shut case. But a decent. cumulative case. I say cumulative, because there would be a number of separate, independent arguments, each of which isn't by itself conclusive, but when taken together offer reasonable support for belief in God. Would such a case be stronger than a case against God, that could be made from the argument from evil and perhaps other arguments? Good question. I'm not sure. But even if the philosophical case for God is stronger than the case against Him, I often wonder if that is the way that God wants us to come to know Him.
I've been advising people that if they want to know if God exists, that they should ask Him. But occasionally I wonder if my advice should be more specific. After all, I believe that God has fully revealed Himself to us in Jesus. I wonder if I should be telling people that they should ask God who Jesus is.
There would be an easy way to test this. Those of you who don't believe in God could say, "God, if you exist, who is Jesus?" If this is the "correct method" of coming to know that God exists and who Jesus is, then God will show you. But what if it isn't the "correct method"? Or what if God doesn't exist? Or what if Jesus is not the full revelation of God to us? Then I would expect that you wouldn't get an answer. Ah, but what would happen if we ask God if He is Buddha? Or some other deity? Should we ask God about those possibilities? I would think that if God exists, and if you are really curious about those questions, then you should ask God about them.
But which God should we ask? I'm inclined to answer, "The God of Abraham, Isaac, and Jacob." But that's because of my Jewish background. For those of you who prefer something less Jewish, perhaps you could ask the "Anselmian God." The God a greater than which cannot be conceived. One who is all good, with no hint of evil.
How would you know that the answer you get is really from God, and not just your imagination or a hallucination? I'm not sure. I suspect that if God wants you to know that He exists and who Jesus is, that He will find a way to make sure you know that it is not your imagination or a hallucination.