Sensing Time

The linear progression of time, that we are moving through time as though it were a viscous medium like water is an illusion.

Why is this moment now, when you are reading this, different from any other? No matter when you are reading this you will always think that the time is "now". In fact people always think that the time is "now" irrespective of the date and time a clock shows! The you of yesterday thinks that it is "now" and yet thinks that the current time is yesterday, just as you today think that now is now. Once you accept that the you of yesterday, and the you of today and the you of tomorrow exist separately and at once, and all of them consider their time "now" then you have a better understanding of the nature of time.

What then makes the present you different from the others? What makes us differentiate between the past and the future?

Our brain provides us with a sense of now. We have a limited knowledge of the past and the future. We might have a memory of yesterday, and a less complete memory of a week ago, and even an less complete memory of a year ago. Any knowledge of our future self is more vague but we might have an appointment or a regular routine, and so have an idea of what we might be doing tomorrow. We might have a more vague idea of what we are doing a week away, and what we are doing in five years might be even more indeterminate. So we have some knowledge of the past and of the future, and this gives us some feeling of time, a sense to detect it. Our memory gives us the strongest memory of the immediate past and it is this that defines our sense of the present. Some part of the brain detects sensory input and feeds this to a short term memory, referring this fact to our consciousness to tell us when the present is, acting like a sense organ that detects "now". A conscious intelligence, like the examples of the appointments and routine will also add to this sense, indicating that even without an inherent feeling of the present, it could be detected in some ways. These things combined create a sense of now, and our experience of time is defined by and created by this sense of it, a sense felt by our body and nothing more. There is nothing inherent in the universe that defines when the present time is.

Every one of our selves at every point in time considers themselves active in the present, but this is the case for every being and all time too. Our past, even the time before we were born is here and as real as any recent past. The fact that our memory of five seconds ago is stronger doesn't make that time any more real than five seconds before we were born, or five million years ago. We are unborn, alive at every point and long dead all at once, overlayed upon each other. Such concepts such as life and death and redundant in this view. Einstien, Archimedes and Elvis Presley are no more dead and no more alive than any of us.

If this is so, why do we have such a strong feeling of time? Why do we feel that today is now, that the past is done and that we can change our future? Why does last week feel more important than one hundred years ago, or one million years ago? These are the result of evolution. Our different memories, short term, medium term, long term, and even terms beyond our life like writing and historical record, have evolved to ensure the survival of our species. Each creature will experience time in a way that best suits the survival of their species.

Could a brain evolve a memory that detects the future? A memory that accurately detects the future is impossible. The knowledge of a future event would allow the possibility of changing that future. Something would have to disrupt that paradox and there are only two options; that a future-memory is unreliable, or that the future could be changed. However, the changing the future would also render the future-memory unreliable, and so there is but one option, that any information from the future must be unreliable.

There is one joker to play however, and that is that the same is true in reverse. Our sense of destiny, that we are able to change the future and unable to change the past is also a biological one. We feel that we can change the future and we feel we cannot change the past. This feeling is also illusory. We are unable to change either, and, as such, a memory that accurately detects the past is also impossible.

Fortunately we don't need perfection. I must conclude that a memory of the future as perfect (or imperfect) as the memory we have of the past is possible.

Mark Sheeky, 19 August 2012