What is the age of the Earth if time does not exist?
Answer by Jürgen Lawrenz
Good question! What a predicament for all of us, not just philosophers, to be told on one hand that time flows, which ought to mean it is a measurable quantity as our clocks show us; or, in the view of eternity, there is no such thing as time.
However, it is only a human dilemma. To understand the world as the theatre where past, present and future rules, we need a constant that hovers over temporality – something that ticks impartially in the background with unwavering regularity, but has no beginning nor end. We take in our stride (or try to ignore) that such an infinite clockwork makes it impossible to identify a moment in time, as likewise it is impossible to assign to any temporal occasion a definite location in infinite space. We need such a constant to deputise for the one thing we don’t have: a reference point at rest in the centre.
And so we devise conceptual makeshifts such as the fabled ‘big bang’, to which we cling as a feature to help us with ontological reasoning. We need this sort of thing so that science can operate instrumentally, e.g. measuring time as well as space by using the velocity of light in a vacuum as a constant. Yet light is also a phenomenon, and so we go round in circles.
Hence the answer to your specific question must be detached from the dubious conception of time as some kind of res fluidum. The age of the earth is simply a number that answers to its orbital motions around the sun, retrofitted to the moment of its ejection from the sun. It is a very inaccurate measure, since the length of each of those years is not a fixed quantity – consider that the very word “year” defines “1 orbit”, which varies constantly even now and compels us to insert leap years every now and then – but only God knows the length of leap years over a span of several billion years!
All this is bamboozling in high degree. Factually regarded the Earth’s age is not measurable by any means at our disposal. Whatever age our scientists derive from the solar carousel must revert to human intuition; and this would not ensure that the numbers associated with the genesis of the solar system are intelligible – if they were doubled or even multiplied by a hundred, would anyone genuinely comprehend the difference?
In sum: Make do. Don’t worry about time and space and how to reconcile their infinitude with a concrete distance/duration with which you can associate empirically. An existent cannot be finite and infinite. In fact, an existent cannot be infinite, as all existents are made of finite parts. But being finite, they must exist in time, i.e. to begin at one time and end at another. And now the only means at our disposal to unravel this question is to consult Einstein’s relativity. However be prepared for more perplexity here, because with “curved space” and “time dilation” the aforesaid problems return with full force.
Not a satisfactory answer to your question, I agree; but I suspect there really is no answer. Which may be one reason why philosophers have struggled with these conceptions ever since Anaximander put the idea of an “apeiron” (boundless cosmos) on the map nearly 2600 years ago.