A reader writes:

As I'm sure you know Rowe's argument is explicitly made by Friedrich Nietzsche, who calls the doctrine "the eternal recurrence" thesis. The problem is, it's provably mathematically false. In mathematics all sorts of things go to infinity without ever repeating.

Another reader:

The idea that you would have to lead your life over and over he thought would be a spur to living a more authentic life. There are problems with this idea.

First is that we do not know if either space or time is in fact "infinite". And then there is the fact that some infinities are larger than others, as Cantor proved mathematically.

For instance the infinite number of whole numbers has to be smaller than the infinite number of fractions. Suppose the infinity of time is smaller than the infinity of space and matter. It would never repeat.

Another reader adds:

Atheistic reincarnation seems to be dependent on a universe that's not only infinite, but self regenerating. If the universe began as an infinitesimally small point and then expands forever into a void, then it may not be so. In that case, entropy increases through the life of the universe and the random events that created who you are, are extremely unlikely to reoccur even in an infinite time-line.

On the other hand, if the universe is in a kind of loop where it expands and then eventually collapses back in on itself, then this reincarnation concept is almost a certainty. Every time the universe falls back in on itself the deck is reshuffled.

Even accepting the fantasy premise, the essence of reincarnation requires that there be something uniquely me-ish about my next incarnation. If I am reincarnated next century as a lizard, that lizard has to have some essence of me to distinguish it from all other lizards. If a physically identical me were to re-occur in some identical recurrence of this universe, it would be a mock-up, not a reincarnation, unless you also suppose a soul or something else eternal, waiting in some heaven for the replays of its earthly existence. And that gets you pretty far away from atheism.

A reader writes:

The problems with Mr. Rowe's argument are three folds. To begin with, no current evidence points to a universe that is infinite in either direction of the time dimension; in other words from all appearances, our Universe is bounded with a specific beginning and a specific end. It may very well be that the cycle of Bang and Crunch is cyclical, but then again it may not; moreover, baring new evidence, the current consensus is that a slow drifting heat-death, not a cosmic collapse, is the end in store for our cosmos. So much for infinite time.

Secondly, Mr. Rowe underestimates the infinite variety possible even with just four partnered amino acids locked in bounded carbon chains. Even when one should have a good chance of genetic "reincarnation"; when the noise of generations is generally small, such an occurrence is unheard of. Children are only removed from their parent's DNA by one generation; in other words, their chances of being phenotypic copies of their parents are much higher than that of the general population if only because they are working from (mostly) the same blueprint, yet how often does a child resemble, exactly, a parent?

To argue that variety is insufficient to allow for "reincarnation" at one generation, but sufficient to allow for it in a 187th cousin 500 years ago is to misunderstand genetics as simple statistics (and to misunderstand statistics, for that matter). Thirdly, he makes the common error of assuming genetics is determinative where, in reality, it is dispositional. Your genes are not "fate". They may grant you a predisposition to be witty, or fast, or towards easier and faster muscle construction, but it is environment and the decisions you, as the product both of genetic variation and infant experience, begin to make almost form the time you leave the womb that determines if and how you will make use of those predispositions. How many children of Olympic athletes become olympians themselves? Where does the great, great, great, great, great, great grandson of Socrates teach philosophy and logic? What new discoveries in physics have been made by Einstein's children, and grand-children, and great-grand-children? All of them were born, to lesser or greater degrees, with the same skill and attribute dispositions as their distinguished ancestors, but few if any of them have followed that ancestor's venerable path. Why is this? Because even if time and genetics are not infinite, choice and circumstance are.

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