Isaac Newton thought that the universe functions like a simple mechanism. A causes B, B causes C, and C caused D. His view was the most intuitive, or that we are part of the big mechanism in the external world, and what we observe around us, is the external world itself, which is as real as it could be. Hume, though pointed out, quite correctly that what we know is that our sensations deliver information to us that we have a hunch has something to do with the external world, yet we do not have any reason to believe that this hunch is correct.
We may yet discover rules that direct Quantum mechanics in deterministic ways, this would lead us back to a mechanistic universe.
also, it only makes sense to talk about this world as an illusion if you have some other world in mind. if we can never perceive this "true reality" then this world would for all intensive purposes BE our "reality". There must be some fundemental difference between the two to really make any sense of alternate and 'true realities'.
We merely know that we have access to the information the senses gave us, but if the senses have collected the information adequately. Kant has suggested that it is not the case as Newton thought, that we are in the world, but the world is in us which is plausible. Newton’s intuitive worldview is manifestly untenable. Newton’s world is finite because it has many attributes. It means it has been created by another entity, because a finite entity is by definition limited. Yet what created this one another entity, another entity? We shall proceed ad infinitum seeking the first cause without having found one. This leads to the absurdity that something came from nothing. Such a thesis could not be true.
causation (in this case, entity --> entity) only makes sense "IN" time. we have no reason to think that holds true 'outside' of time (the multi-verse 'bubble' itself). second, we dont need an infinite regress, chaos can arise out of order. if we roll 6 dice 50,000 times, we have a greater than 5/6 chance of getting 1 2 3 4 5 6 eventually. its almost inevitable that either smolen selection or chaos inflationary properties could be reached. the chaos could be vast enough that its practically infinite to us,
though not actually infinite (though it all could be infinite, no way to tell right now). chaos makes the most sense as the originator because its the simplest entity imaginable (with no order) and it doesn't need a cause. the first thing will always be a "just was", because there is nothing happening before it (causation only makes sense IN time, once time has started). there cant be anything that sits before the timeline to "cause" because then that thing would be outside of time.
Therefore Newton’s claim that the world of our finite experience is as real as it gets must be false. If we posit that the ultimate reality is infinite, we shall have an opportunity to explain the first cause of the universe. What is infinite is by definition without limits. Therefore what is infinite is all that exists. Thus it by definition has no limits, that means no constrains of time. Therefore it has always existed and will always exist. It also by definition has no creator because it is all that exists. Our world is not infinite, therefore it is an illusion. It is however, our apriori representation of the infinite realm. Because our mind is unable to properly process the infinite realm, it unconsciously represents it in terms of what it can properly process. Hence, this is a clear-cut example of an apriori faculty within the human mind. When a baby is born, it unconsciously translates the infinite realm into finite terms and as a result of this envisages the world as we know it. This is not to be counted as knowledge because the representation of the finite world as we experience is unconscious rather than conscious. In other words, this merely represents the opportunity one has to experience the external world directly. We can conclude that three entities are completely apriori, the vision of the external world or the opportunity to experience it, our physical functions and the potential to function in a certain physical or a psychological way.
the "innate"ness of the brain or perceiving faculties is simply due to the arrangement of the machinery. the brain begins to collect data, because thats what the machinery does. the geometry of the machinery in the space-time continuum simply determines that this is an arrangement that collects data. its not some magical property that needs to have some starter software. the software is created and written as data is gathered. if we were born with rocket launchers, would you say that 'opportunity to launch rockets' was aprior?
"In Kant's own terminology, space is nothing more than a 'form of intuition [i.e., perception]'. Kant employs a similar argument to conclude that time, too, is a mere form of intuition. Space and time are features of the phenomenal world - the world as it appears to us - only. The noumenal world - the world of things as they are in themselves - is aspatial and atemporal."
Time is simply our minds building the perception of the symmetry breaking 4th dimension. so in a sense, time is intuition. Space however, is there. there is no getting around that! our brains may not for example, notice the ENTIRE light spectrum, but that doesnt make the light spectrum we do notice some sort of false reality...