Reality is subjective. Entirely subjective. Each individual filters the information they receive from the world around them based on what is important to them, their values, cultural influences, upbringing, conditioning... The human brain cannot process all the information it receives from the five senses simultaneously and so it picks those things that are most important, most pertinent to the individual, and discards the rest. The filters that I apply to what my senses tell me are around me are unique and entirely different from yours or anyone else's. What we call reality can only really be what we as an individual perceive as reality....and my reality, as is yours, is entirely my own.