@Danser
Good example and answer. That really helps
However, is God comparable to the sex of a human? See what I mean? I like your analogy, but is it comparable?
On another note, couldn’t the ‘other force’ be, say, an undiscovered gravity field? (M-theory) or perhaps an energy field, as some scientists suggest?
Perhaps I am taking this too far, though.
Well, why not try to think of a comparable analogy yourself, I’d say go for it.

The point, of course, isn’t that God is like the sex of a human, the point of the analogy is just to show that we cannot be eternally prevented from making a rational inference, simply because of what may, possibly, theoretically be discovered in the future, especially if, as in this case, we have very good reasons for thinking that we have accounted for all the alternatives. To insist we hold off forever would make any rational inference impossible, not just about God, but about anything.
The other thing to keep in mind is the premises of the argument. When someone makes an objection, make sure you know which premise of the argument, the objection is really aimed at, even if the person making the objection does not know themselves.
Here’s the Kalam Cosmological argument
1). Everything that begins to exist has a cause
2). the universe began to exist
3). the universe has a cause
4). the cause of the universe an un-embodied mind (a couple steps to get here, see my first post).
When someone proposes energy as a cause, this is not aimed at point number 4 (the cause is a mind), but at point 2. energy is part of the physical universe, so either it had a beginning or not. If it did, then that still brings us to point 4, that its cause had to be God. If they say energy did not have a beginning, then this runs into conflict with the arguments (2 philosophical, 2 scientific) showing that the universe had to have a beginning. Same with an undiscovered gravity field.
If they say “well, what about an immaterial, atemporal, non-abstract object, non-personal cause.” The answer to that is easy: it’s just empty words. Like talking about a non-male, non-female, non-androgynous sex. If we have good reason for thinking we’ve accounted for all the possibilities, then just putting the word “not” in front of all of them and saying “couldn’t it be something besides them,” is meaningless. If there is another alternative, they are free to suggest it, but otherwise, we are free to draw the obvious conclusion.