The concept of simultaneous causality is what theists use to save themselves when making the cosmological argument from the logical problem of causes preceding their effects when the effect is the beginning of time itself. They claim that god somehow caused the universe to exist at the same time as the effect took place. But does simultaneous causality really exist?
Immanuel Kant, the famous 18th century German philosopher gave a well known example of simultaneous causality. He imagined a ball resting on a pillow. The impression of the ball on the surface of the pillow is a simultaneous cause and effect according to Kant. But we all know that the ball must be dropped onto the pillow first, and as the ball drops, the impression in the pillow deepens. So the cause does precede its effect in Kant's example.
Some theists have proposed the idea of a ball resting on a pillow existing in that state eternally, then the cause would not be said to have preceded its effect. This idea, some theists claim, saves the simultaneous causality hypothesis from the rigid manner of a temporal world where causes always precede their effects. But is this a practical scenario? And does it compare to the origin of the universe?
First, what does it mean to exist in a state eternally? Does it mean eternally in the same sense as the block universe is eternal? Suppose we can imagine a block universe consisting of just a single ball resting on a pillow that exists in that state unchanging. Would this be an example of simultaneous causation? Well, a block universe doesn't begin to exist in an ontological sense and once any kind of tenseless theory of time is acknowledged, it then invalidates the cosmological argument.
So a presentist or tensed theory on time must be acknowledged in order to safely claim simultaneous causation to exist. How then can something exist from "eternity" under presentism? I suppose the theist will propose some sort of static or frozen timeless state that precedes the existence of time, but I struggle to grasp the idea of simultaneous causation in this scenario. If the cause is eternal, then the effect must be eternal too if they're simultaneous. One could not precede the other; they'd be frozen in time, unchanging. But if the effect can exist from eternity, why does it need a cause? An eternal effect seems to render the need for a cause as redundant.
Second, how can this be related to the origin of the universe? I ask this, because I don't see how the cause of the universe and the effect of the universe beginning can exist from "eternity" in the same way that the analogy is poised, given a presentist theory on time where temporal becoming is real. Does the cause and effect "begin" to exist from nothing temporally? If so, doesn't that make it existing from eternity actually impossible? And wouldn't god have had to will it to exist first? Or does god willing the universe coincide with the effect of the universe beginning to exist too? And how can we know what caused what if the cause and the effects are temporally simultaneous? A cause and effect existing eternally kind of reminds me of the idea of the universe causing itself to exist because the universe's cause and effect would exist simultaneous. Or, if existing from eternity is possible, why can't the earliest state of the singularity exist from eternity until it started to expand and create time along with it? The theist might say that a mind is needed to will time into existence allowing change, but then we're back to the idea of god's will existing from eternity, making it impossible that he could've chosen not to create the universe. And unless you want to propose some kind of 'metaphysical' time that is pure theological conjecture, our universe would not be contingent.
One problem with simultaneous causation is that if A can cause B at the same time, what's not to say that A can cause B which can cause C at the same time too? You can then imagine an infinite amount of causes and effects and say they all occur simultaneous and end up with a what can appear to be nonsensical. If an infinite number of simultaneous causes and effects isn't possible, then one occurring simultaneous probably isn't either. Temporal procession between effects and their cause prevents this problem. To say that a cause doesn't have to precede its effects opens you up to these kinds of conundrums.
So is it logically impossible that simultaneous causation could exist? I lean towards yes. If an infinite series of simultaneous causes and effects is indeed illogical, than simultaneous causality is not logically possible. If the theist can somehow reconcile this with metaphysical reality, then I'm open to the possibility that simultaneous causality exists. Otherwise, since theists who make the cosmological arguments, like William Lane Craig and his minions, stress the logical contradiction of an actual infinite existing, they must be able to reconcile the same paradox that simultaneous causality produces. I personally don't see a problem with an actual infinity existing, but that can only exist, as far as I know, under the eternalist or tenseless theory on time, which is incompatible with any cosmological argument. And if the best analogy of simultaneous causality requires that you propose a cause and effect existing from "eternity," than an effect existing eternally doesn't in fact require a cause, thus making the cause redundant.
Finally, one common false dichotomy that theists try to corner atheists with on the origin of the universe is to say that it could only have been caused one of two ways. Either (1) the universe caused itself to exist, or (2) a spaceless, timeless transcendent being caused it to exist. For option 1—the option theists believe the atheist must make is contradictory, because in order to cause itself, the universe would have to exist before it exists. Logically that's the equivalent of saying that I was born, before I was born. Not too logical aye? But no atheist has to be committed to believing that the universe caused itself. And the theist who pushes this false dilemma is in effect, conceding that causes must precede their effects, since the only option they're giving the atheist is the claim that the universe would've began to exist, before it began to exist.