My Goal here is to give the shortest proof of an uncaused cause using deductive arguments only. One could call this an ontological argument, but please do not confuse this with Anselm’s ontological argument.
Premise 1. Absolutely nothing cannot be a true state of affairs, because there is no truth in absolutely nothing and a true state of affairs is always about something. In other-words the concept of there actually being absolutely nothing and at the same time being true is meaningless like a square-circle.
Premise 2. Therefore an necessary being, an uncaused cause, must necessarily exist, for if only unnecessary beings existed then it would be possible for absolutely nothing to exist, which conflicts with premise 1.
Conclusion: A necessary uncaused-cause exists.