I started considering the question ‘how do we know what’s real’ when I was in my teens. Then the Matrix came out years later which got me thinking again. In eastern traditions they have the idea of ‘maya’ or illusion. The earthly existence is thought to be essentially illusory. Shakespeare wrote ‘all the worlds a stage’. I think we humans intuitively understand the illusory nature of reality. And striving for higher consciousness to break through the veil so to speak.