If causality isn't so what would be rational?
Causality as evidence for a Creator God, you mean?
The version I know of that claim goes along the lines of "everything has a cause, so existence itself can be no exception, therefore there is a first cause, which is itself uncaused, which should therefore be divine in nature".
Ironically, such a claim is self-contradictory and only appears logical
if you take for granted that there is such a thing as a creator God. Far from being a logical argument, it is a circle of premises that attempt to evidence each other without ever reaching solid ground.
What is the contradiction? The symultaneous assumptions that
everything has a cause and that
there is an uncaused causer, a first cause.
That may sound conforting for those who have the natural tendency to be troubled by the question of a first cause, or who have been driven into conforming to that expectation by being scared into it by a (usually) Christian or Muslim education.
But it makes no logical sense at all. It relies on a supposedly reliable rule
and on the necessity of the existence of a single exception to it
and on the assumption that said exception must be sentient
and all-powerful.
That is why it is not a good argument for believers, and essentially worthless for attempts at converting non-believers.
But that is ok. No one should feel troubled by disbelief. Not believers and certainly not disbelievers.
As a side note, you may want to learn about tangential concepts such as apatheism. It may be useful to help you realize that the dichotomy of "belief vs unbelief" is actually a very rough representation of what is ultimately a very minor, inconsequential matter.
There are many importante subjects in life. Whether there is a God is most definitely not one of those.
Which and how many deities (if any) one believes in is a strictly personal matter and it is not really very important to be "right" about that even by that perspective; it
really is ok to keep changing one's opinion on the matter all the time, even randomly or by a whim, if one wants to.