In the introduction, I mentioned Parmenides (par-meni-deez). Parmenides was a Greek philosopher who was born in Elea during the 5th century BCE. His only known work is a poem called 'On Nature' where he distinguishes two views of reality: the true one ("The Way of Truth" - aletheia) and the one we see ("The Way of Appearance" - doxa). Although some of the work is missing, and the interpretation varies, his basic message was that the true reality was a timeless, uniform, unchanging unity, which he called 'The One', and that our perceived reality was a deception created by our senses. Although these views received great criticism, bordering on ridicule, they are credited with influencing much of Western philosophy.
When I came across the work of Parmenides, shortly after completing the first edition of this work, I was stunned by the insight of a philosopher from such an ancient time; insight that runs counter to our physical intuition. Given that this same view of reality is far from accepted in our modern era, where could he have possibly received his inspiration?
The work includes a proem which describes a young man being carried in a whirling chariot to the sacred temple of an unnamed goddess from whom the rest of the poem was received. The goddess supposedly informs him that "...It is meet that you learn all things - both the unshakable heart of well-rounded truth and the opinions of mortals in which there is not true belief".
Fast-forwarding to 1945, John Archibald Wheeler and Richard Feynman (his research assistant at the time) investigated a time-symmetric solution to the electromagnetic field equations. This ‘Wheeler–Feynman absorber theory’ made perfect sense as there was no reason to single-out a preferred direction of time in the equations. The theory achieved some success and provided a cleaner interpretation of certain issues in quantum mechanics. However, it was largely abandoned because of the conflict with our physical notions of causality. Since cause-and-effect was considered sacrosanct then the theory could not be reconciled with perceived reality. This is a great example of how a radically different view of reality – as described in this work – can influence the advancement of our knowledge. Some promising later work was done by others to take this theory further but it still sits on the sidelines as far as mainstream physics is concerned, despite its potential for new insights.