Where is your vocabulary? Can you inventory it? We only experience the effects as the sentences we hear and see; never our vocabulary en masse.
Analogous to 'Brownian Movement'. Robert Brown only saw the effects of molecular motion moving the pollen grains, he did not see the subatomic particles causing the motion.
In the same way, we experience emotional suffering, dysfunctional behavior, mistakes, stress, etc. These are effects of subliminally believing some thought-images are real, even if false.
There's another subliminal 'process' I have been referring to, "innate natural intelligence". We cannot observe that 'process', only experience the effects as well being, psychological health, creativity, insights, intuition.
No one sees evolution either, we see effects as change. We don't see gravity, we see things fall, (Newtons apples).
Physicists deal with quantuum level from "outside" with theories, hypothesis, etc. We can access (introspectively) that invisible level 'process' (innate natural inteligence) from "inside" perspective.
If, as a result of reading this, you experience aha/insight, it comes from 'innate natural intelligence'.
If, no insight, then this is just another academic theory 'to you'.
For those of you who want substantial/observable data, your out of luck. In this electronic age, the invisible is where 'it's at.'