# Is there a better answer to this argument claiming the impossibility of time extending infinitely into the past?

My friend claimed that time cannot extend infinitely into the past. He explained:

"If an event A will happen in 10 years, when do you expect it to happen? In 10 years. But if event A (such as the event of our conversation) will happen in infinitely many years, when do you expect it to happen? Never. Therefore, if time was infinite into the past, this conversation would never occur."

First, I find this argument extremely weak and totally unconvincing. Just because something doesn't make sense to us is only "infinitesimal" evidence that it is false.

Secondly, there is another issue that I find with it that I don't fully understand myself, but I have a hunch it is right. Basically in his argument he is implicitly assuming that he can pick a point P on a timeline and view any other point from the POV of point P, including points that are infinitely far away from P (which doesn't really make sense by itself). But I have a hunch that this ability to pick a specific point P on the timeline is exactly what he is trying to disporove.

Can somebody please help me understand and flesh out my own argument, and/or offer a better alternative?

• Could you edit the quoted sentence. Does "you expect event A to happen 10 years" mean "you expect event A to happen every 10 years"? And what is "such out existence"? Currently I do not understand what it means, let alone if it is an argument, weak or strong. Does it mean that we "expect" our existence to happen "never" if the universe existed for infinitely long time? If so, the response is that our "expectations" are irrelevant, and somebody like "us" might have been happening every quadrillion years anyway. Jan 27, 2017 at 19:18
• @Conifold Apologies. I edited it, is it more clear now? To answer your specific questions: I made typos in both of those sentences. The first phrase should've been "you expect event A to happen in*10 years", and the second phrase should've been "such as *our existence". To make it more understandable, I have replaced this second phrase with "such as the event of our conversation".
– Ovi
Jan 27, 2017 at 19:35
• Your objection (I think) can be rephrased as follows: there are no points "on the timeline" that are infinitely far from each other, even if the timeline itself is infinite, so there is no point P from which "infinitely many years" can be counted. But there are far more basic issues with this "argument", like analogizing infinite to finite (for continuous probability all individual outcomes have probability 0, yet one of them still happens), or even the initial non-sequitur "if an event A will happen in 10 years, we expect it to happen in 10 years"??? Jan 27, 2017 at 19:50
• I like the mathematical example of the real line, which extends indefinitely in both directions. Put a big tape flag at the point marked "2017". Here we are, with unboundedness in the directions of both past and future. Works for me. Note that even if the past is infinite (or more accurately, unbounded) the distance between any point in the past and now is a finite interval of time. Maybe that's just how the universe works. Jan 28, 2017 at 2:21