I had a thought yesterday evening that I can't get out of my head, now. This lead me down a twisting, turning avenue of questions and answers which lead inevitably to more questions, as such philosophical musings are wont to do, and so I come here now, to my book, to put these thoughts down so that they might be taken from my already too-full-to-be-bothered-by-it-head.

So, here it is. The thought, or rather, the question.

What is a door?

This question at first glance seems simple, straightforward enough. If one were to take a look into the average dictionary, one would find the following definition:

door
d?r
noun
a hinged, sliding, or revolving barrier at the entrance to a building, room, or vehicle, or in the framework of a cupboard.


There, question answered, on to the next one!

But it's not that simple.

A door exists for what purpose? The layman would say, "Allow or deny one to pass into or out of a place."

And, that is very true. That is the purpose of a door. It is a way in and out, or a way to keep one out. But what is a door when it is ignored? For instance, if tomorrow all the people in the world were suddenly granted the ability to instantaneously appear wherever they desired via teleportation or some such nonsense. Doors would still be there, as they are described in the dictionary. A slab of wood or other material on hinges. But, they would likely go unused. Do they still exist, if their purpose is denied?

That is the root of my problem with the door. Is a door the physical description one reads in a dictionary, or is it the essence of passing into and out of a place? In the olden days, doors were sometimes referred to as portals, after all. And therein lies the confusion. Is a door a portal? Is a portal a door? Are they one in the same?

All portals can be doors, but not all doors are portals?

I cannot, for the life of me, come to a definitive answer.