E
ethereality
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philosophyofreligion.info summarizes the defense of this premise that the past is finite.
It appears to me these are all the same argument, simply phrased in three different ways, which I’ve recently encountered again:
Anonymous:
I think all these formulations of what is essentially the same argument fail due to forgetting one’s definitions: One is introducing the contradiction into the scenario by trying to start at the beginning of an infinite past and then counting one’s way forward. The argument semantically, logically, doesn’t work to refute an actual past infinity because it neglects what a past actual infinity means. It says, “Let us start at the first element of this set which, by definition, has no first element.”[1] That is where the error is introduced into the argument.[2]
So this argument does not prove the kalam argument’s second premise. Yes, you arrive at a contradiction if you try to select the first element of a set which has no first element, because you’ve introduced the contradiction by assuming it to the object in question. However, it is perfectly consistent to look back at the past from the present and understand that each moment had one before it, just as you can look at a long railroad track, stretch of road, or ocean, and recognize that it continues beyond the furthest point that you can see, and that if you continued, you would find more of it. I don’t have to walk the length of Route 66 to know it’s there – nor do I have to do so to appreciate its length: People living geographically along it can each build a portion near where they live and we can obtain its full length piecemeal through the limited contributions of those along it.
It is frightening to suppose that an actual infinity exists – and this same realization of something wholly other from our finiteness is one reason for the biblical “Fear of the Lord” – but it is not self-contradicting nor clearly false. It is unimaginable, but not inconceivable.
Switching gears, as I alluded to above, the proper consideration is not whether a single element can span (or traverse) an infinity, but whether an infinite number of elements can. Regarding single beings, only one existing in eternity (outside of time) can span an infinite past (traveling through all of time all at once), but an infinite number of finite elements can also do so (each finite element traversing a finite length), just as x meter-wide planks can fill in a fence of length x meters).[3]
Additional Thoughts
[1] As another demonstration of this argument’s logical error, we believe our souls to be eternal, that we have an “infinite future” as Jimmy Akin said recently, perhaps on the last day of Catholic Answers’ pledge drive. You can deny this infinite future using precisely the same argument: Start at the last moment of the infinite future and then count your way back to the present. “It can’t be done! Therefore we cannot have an infinite future.” No, the problem is that you are contradicting what ‘infinite’ means: For an infinite future, there is no “last point” from which you count back to the present. Likewise for an infinite past, there is no “first point” from which you begin counting to the present.
Of course I understand the qualitative difference between past and future being actual rather than potential (from the perspective of going forward), that one seeks to prove that one cannot have an actual infinity whereas a potential infinity is fine (because it is not actual), but my point here is simply to show the logical problem with the argument.
[2] All the arguments are about counting in this way, just counting with different methods: numerically in abstraction, or equivalently via grains of sand or steps taken. So the three formulations on that site are the same argument committing the same error.
[3] Or, if you like, N planks of width M meters filling in fence of length L, where M = L/N. Thinking about infinity is getting my physics gears going…
It appears to me these are all the same argument, simply phrased in three different ways, which I’ve recently encountered again:
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Trent Horn has likewise repeated the third argument about traversing an infinite past (“we could never arrive at the present”) on the air. I am so frustrated by seeing this error that I am here begging for resolution, either a clear answer on why the rebuttal I will give is wrong, or vindication that I am correct.the fact that there is a today proves there was a beginning. The idea of an infinite finite is absurd. Imagine a lady opening a flower shop. If she had infinite flowers to count, she could never open her flower shop. Just the fact that we are experiencing a “now” that is in motion toward a “tomorrow” and from a “yesterday,” proves there was a beginning.
I think all these formulations of what is essentially the same argument fail due to forgetting one’s definitions: One is introducing the contradiction into the scenario by trying to start at the beginning of an infinite past and then counting one’s way forward. The argument semantically, logically, doesn’t work to refute an actual past infinity because it neglects what a past actual infinity means. It says, “Let us start at the first element of this set which, by definition, has no first element.”[1] That is where the error is introduced into the argument.[2]
So this argument does not prove the kalam argument’s second premise. Yes, you arrive at a contradiction if you try to select the first element of a set which has no first element, because you’ve introduced the contradiction by assuming it to the object in question. However, it is perfectly consistent to look back at the past from the present and understand that each moment had one before it, just as you can look at a long railroad track, stretch of road, or ocean, and recognize that it continues beyond the furthest point that you can see, and that if you continued, you would find more of it. I don’t have to walk the length of Route 66 to know it’s there – nor do I have to do so to appreciate its length: People living geographically along it can each build a portion near where they live and we can obtain its full length piecemeal through the limited contributions of those along it.
It is frightening to suppose that an actual infinity exists – and this same realization of something wholly other from our finiteness is one reason for the biblical “Fear of the Lord” – but it is not self-contradicting nor clearly false. It is unimaginable, but not inconceivable.
Switching gears, as I alluded to above, the proper consideration is not whether a single element can span (or traverse) an infinity, but whether an infinite number of elements can. Regarding single beings, only one existing in eternity (outside of time) can span an infinite past (traveling through all of time all at once), but an infinite number of finite elements can also do so (each finite element traversing a finite length), just as x meter-wide planks can fill in a fence of length x meters).[3]
Additional Thoughts
[1] As another demonstration of this argument’s logical error, we believe our souls to be eternal, that we have an “infinite future” as Jimmy Akin said recently, perhaps on the last day of Catholic Answers’ pledge drive. You can deny this infinite future using precisely the same argument: Start at the last moment of the infinite future and then count your way back to the present. “It can’t be done! Therefore we cannot have an infinite future.” No, the problem is that you are contradicting what ‘infinite’ means: For an infinite future, there is no “last point” from which you count back to the present. Likewise for an infinite past, there is no “first point” from which you begin counting to the present.
Of course I understand the qualitative difference between past and future being actual rather than potential (from the perspective of going forward), that one seeks to prove that one cannot have an actual infinity whereas a potential infinity is fine (because it is not actual), but my point here is simply to show the logical problem with the argument.
[2] All the arguments are about counting in this way, just counting with different methods: numerically in abstraction, or equivalently via grains of sand or steps taken. So the three formulations on that site are the same argument committing the same error.
[3] Or, if you like, N planks of width M meters filling in fence of length L, where M = L/N. Thinking about infinity is getting my physics gears going…