Absence of evidence, is evidence of absence.
If it wasn’t, then there might be an elephant in your room, big foot in your backyard or Nessie in Loch Ness.
Now sure, we can’t rule anything out entirely, perhaps Nessie lives on another planet or dimension, occasionally teleporting from there to Loch Ness, or maybe she’s wearing a cloaking device, or perhaps she just got really, really lucky and evaded detection by scientific equipment hundreds of times.
Still, we can at least conclude that in all likelihood, a Nessie we’re capable of interacting with, that isn’t supernatural, preternatural or sci fi, doesn’t reside in Loch Ness.
Well, the same goes for anything, including causality.
The more we thoroughly look for something, and can’t find it, the more likely it’s not there, at least in any meaningful sense if at all.
It’s not any easier to be sure something is, than isn’t, for what appears to be, could always be illusory somehow, just as what appears not to be, could always be elusive.
You’ve just unnecessarily limited your perception of what’s possible for you to know.
You’ve said I can know what is, but what not what is not.
Take gravity for instance.
On earth at the perceptible scale, gravity appears very reliable, but at the quantum scale, gravity, or whatever they call the force of attraction at the quantum scale, isn’t very reliable, nor is it at the interstellar or galactic scale.
Scientists will very reluctantly and with a great consternation and reservation admit the force of attraction at the quantum scale is partly acausal, but they won’t admit galactic/interstellar gravity is partly acausal.
There’s far more gravity in some regions of the cosmos than their models predict there should be, and they’ve invented an unfalsifiable entity, dark matter to explain it away.
Isn’t the simpler explanation gravity isn’t absolute, rather than concocting unfalsifiable entities?
When we discover something orderly, we agree it’s orderly, we don’t assume it’s really disorderly, and wait for more evidence to prove it’s disorderly, so why assume something is covertly orderly when it’s overtly disorderly?
Why is disorder in the physical, and the psychological realm, never a possibility?
If you won’t even entertain its possibility, of course you will never find it, and scientists don’t entertain it, for they’re bound by their metaphysical assumptions.
There are countless examples of scientists thoroughly looking for a cause, any cause for a long period of time, sometimes centuries, even millennia but not finding one.
Whenever they can’t find one, they point to all the instances where a cause finally turned up after a long period of searching, but they don’t point to instances where a cause never turned up, or where what they thought was the cause, turned out not to be.
There are few, if any examples of scientists looking for freewill/whatever you want to call it, transgressions of the so called laws of nature, and finding one, because again the metaphysicians of science said it’s impossible, we must have law and order, right?
Wrong, while some things may be more probable than others in light of observational evidence, all things are possible, except for something strictly contradictory.
The idea the cosmos has laws it obeys is an artefact of our Judeo-Christian, Platonic and Aristotelian thinking.
We’ve done away with the need for a lawgiver, but not for laws.
Science isn’t fully experimental, if it was than every possibility would be on the table, the metaphysicians of science won’t allow us to entertain certain possibilities, freewill and genuine spontaneity in the cosmos is one of many of them, but there are many others.
Presence of evidence isn’t evidence of presence, at least not necessarily.
As we’ve seen, even in a perfectly random system, some order is not only possible, but probable, in fact it probalby isn’t perfectly random if there isn’t some order.
While a random system ought to produce some order, most of what it produces ought to be disorder.
But for all we know the cosmos is mostly disorder.
There’s a ton of stuff that we think we can explain, but there’s also a ton of stuff we can’t, the latter we assume is ultimately explicable, rather than assuming the former is ultimately inexplicable.
Humans are obsessed with order and what we think we know because it’s practical to be and makes us feel secure, so there may be far less order than we realize, and this is true of most scientists too.
While there are scientists that study randomness on paper, and perhaps in nature, these scientists are the exception, they don’t represent the majority of scientists, and I doubt they’ve devised a systematic way of measuring how much disorder there is in the cosmos, they probably only measured it within a particular realm, or the theory apart from any data.
So there may be far more disorder than order in the cosmos, and that minority of order too might be a by-product of perfect randomness.
We can go on our intuition, and say, well there seems like there’s a lot more order and things we can explain than not, but that is not a philosophical or scientific argument, it is just an opinion, and while opinions have validity, they’re not definitive or proof positive of anything.