That is one way to define religion. It is not generally how scholars of the subject define it.
I know a lot of Christians who don’t want to admit Christianity is a “religion,” either. Again, it all depends on how you define it. I think the best approach is to take a very wide definition. The approach that you are taking–which your Buddhist friends appear to share–is to use Christianity and other Western monotheistic religions as the base for the definition of “religion.”
Not knowing your Buddhist friends, I can’t be sure why they take this approach, but my guess would be that they don’t want you to assume that their tradition has the same basic assumptions and claims as Christianity. They may be concerned with the kind of knee-jerk hostility demonstrated by many folks on this thread–the automatic classification of statues of Buddha as “idols,” for instance.
It may be that the entire modern scholarly enterprise of describing and classifying specific members of a broad genus called “religion” existing all over the world was misguided from the start. But what you need to be clear on is that you are in fact rejecting that entire enterprise when you say “Buddhism isn’t a religion.” You are basically saying that unless you are a monotheist (at least in the modified sense in which many Hindus are monotheists) you don’t have a religion.
That would exclude Buddhism, but it would also exclude ancient polytheistic traditions, Chinese religions, etc. You are essentially saying that unless you are some kind of monotheist you don’t have a religion. (I say “some kind of” because of course Hindus recognize all kinds of gods who are manifestations of or emanations of Brahman.)
There’s a doctrine of rebirth. There’s a whole complex system of heavens and hells and various other worlds into which one can be reborn. So I’m not sure what you are talking about here.
Not in the Christian sense. But there is certainly a human predicament (extending beyond the frontiers of this life, contrary to what you say) from which we need deliverance. In that sense there definitely is a doctrine of salvation.
It is precisely because I have “dug deeper” that I question shallow definitions of religion.
Religion scholars generally are very cautious about defining religion. Indeed, some would say that the entire discipline is in crisis right now, because the old (19th and earlier 20th century) assumption that there is a generic thing called “religion” of which particular religions are instances has come under a lot of scrutiny.
For more on this, you might read
this article by Paul Griffiths, a Catholic theologian who is also an expert on Buddhism.
Aren’t you contradicting yourself? How can things that are “completely opposite” be “intertwining”?
Since you define religion as belief in a Creator God, it would follow that philosophy has nothing to do with such belief. St. Thomas Aquinas would be very surprised to hear this, unless by “belief” you mean specifically what Aquinas calls “faith”–that is to say, a belief that cannot be fully proved by reason. But this raises problems, since as Aquinas points out something that is held by one person as a matter of faith may be held by another as a matter of reason (such as the existence of God, or God’s creation of the world–though not, Aquinas thinks, the temporal beginning of the world). So for Aquinas philosophy and theology (he would use “religio” for a way of life or form of worship, not a set of beliefs) have overlapping subject matter but different methodologies. Maybe that’s what you mean by your “completely opposite but intertwining” statement.
Edwin