The second cornerstone of Physics is the word exist. Physics attempts to discover and identify that which exists and to objectively explain actual mechanisms of the world around us.
Indeed, the strategic word exist is invoked in practically every paragraph written and in every dissertation given. Therefore, defining exist is neither an option nor a trivial exercise in semantics. Physics demands a rigorous definition of this ubiquitous term. We cannot ‘do Physics’ without it.
In order to arrive at a scientific definition of the ellusive word exist, we must first establish a couple of prerequisites. One of those is the word definition itself. A scientific definition is one that can be used consistently, meaning: rationally.
definition: a set of criteria that limits the extent or usage of a word
distance: separation between two objects
location: the set of distances from one object to all others
motion (to move): two or more locations of an object
exist: an object that has location; physical presence
It is common in ordinary speech to casually say things such as ‘love exists’. In Physics, on the other hand, existence is a property restricted to objects. Only an object can be a noun and serve as the subject of a scientific statement. Concepts are not nouns for the purposes of Physics. In Physics, we avoid saying, “The orbit of Jupiter.” We say, “Jupiter orbits.”
The word exist cannot be applied to concepts because concepts lack both: boundaries and location. There are no distances between concepts or between concepts and objects.
concept: a word that invokes or embodies two objects or two words treated as objects
A concept is a relation established between two objects by a conscious entity. Out ‘there’, in the darkness we call space or ‘the Universe’, there are no concepts floating around. There is no such ‘thing’ as a standalone concept that we can draw on the board by itself. Existence consists solely of objects. It is this ‘real world’ that Physics attempts to unravel.
All words in the dictionary can be categorized either as objects or as concepts. There is no third category. A good rule of thumb to quickly place a word in its proper category is that an object has shape whereas a concept doesn’t. If it can’t be drawn or illustrated, it is a concept!
It is pertinent to clarify that no one has to agree to these definitions. The naysayer, skeptic, or the devil’s advocate has a single recourse: he must define exist in the alternative. Only if the physicist defines this strategic word can the audience follow his presentation.