We live in a world of transient things – the 10,000 things as Lao Tsu called them. Things are put together, reach some sort of maximum capability, and then fall apart, either gradually or suddenly. Of course, this includes you and me.
It is the nature of matter to always be moving and changing its forms. In fact, change is the name of the game where matter is concerned, and so it would be silly to look for some kind of stability in the world of matter. If this was the only world we knew we would need to resign ourselves to constant change – a constant becoming as Plato described it. Fortunately, this is not the only world we know, we also live in a world of ideas. Now, before hardened materialists protest that ideas are just circuits firing in the brain, let’s establish a few things. Material objects change with time. Even the mightiest and most long-lived material objects change with time – the sun will die in a couple of billion years, Mount Everest will be weathered, and our galaxy, the Milky Way, will collide with the Andromeda galaxy.
There are two kinds of idea. Roughly speaking, there are those associated with material things – the function of an airplane, the design of dwelling places, and even how material things should behave – morality for example. When an idea is attached to a material thing it changes as the thing changes. But there is another class of ideas that do not relate to material things – the idea of a triangle is a good example. The definition and properties of triangles are as true today as they were thousands of years ago, and as true as they will be thousands of years from now. There are no triangles in nature – they are not material things. The geometry of triangles does not disassemble, wear on the edges, decompose, or change in any way with time. The idea is eternal – outside of time.
Readers of Kant will know that mutable ideas pretty much correspond with a posteriori knowledge, or ideas associated with material experience. Eternal ideas, those outside time, correspond with a priori ideas – those which are part of our mental makeup. Without digressing too much, it has often been asked why mathematics particularly describes the physical world so well. It does so because the space-time continuum we experience and mathematics are both produced by the mind, and so we should expect there to be some compatibility.
The notion of an entity that exists outside of time and space is a big deal (in my opinion). The idea of a triangle does not occupy any space and does not change with time. I really don’t care if people want to say that ideas are just mirages in the brain, it changes nothing. We can know a class of entities that exist outside of space and time. I think they are worth getting to know.