Not empirically. There is no outside observer to take and compare notes during the double multiple Graham-years wait until two returns had passed. God, who might volunteer for the job, is too busy trying to prove that he exists.
Nietzsche made a few elegant logical attempts at proofs in his notes. However, he was never so convinced of them as to publish them. Here are two of them from the book of tentative notes published by his sister (The titles are mine):
The Will to Power, note 1066
"If the world may be thought of as a certain definite quantity of force and as a certain definite number of centers of force--and every other representation remains indefinite and therefore useless--it follows that, in the great dice game of existence, it must pass through a calculable number of combinations. In infinite time, every possible combination would at some time or another be realized; more: it would be realized an infinite number of times. And since between every combination and its next recurrence all other possible combinations would have to take place, and each of these combinations conditions the entire sequence of combinations in the same series, a circular movement of absolutely identical series is thus demonstrated: the world as a circular movement that has already repeated itself infinitely often and plays its game in infinitum."
My "proof" is experiential. It comes from the sense and feeling of the non-neurotic solidity
of existence, of awareness.
It is indicated in the following paradox:
If death is real, why are we so calm?
If death is not real, why are we so nervous?
There is a yin-yang dynamic going on here. The abyss, the personal extinction that would last forever, if it were true, would be too devastating and paralyzing psychologically. Death is very real. In a near car accident the adrenaline rush of our body tells us it's very real. But the extinction that our predictive minds first saw 40,000 years ago, is not eternal. Yes, a very, very, very big number of years, but not eternal. The world as it is now returns. Everything we are aware of, every wandering moment of awareness is not fleeting but eternal, repeating itself eternally and us with it.
In the end a rock solid proof of eternal recurrence is elusive, but this is the case for all "knowledge", theories and philosophies. The only solid rock certainty, put forward by Descartes, "I think, therefore I am" is almost true but not quite. Thinking is the most ghostly of activities and at bottom is always "trying to figure out how to survive my death", always propping up the belief, "I'm not going to die." . Despite its wandering nature, awareness is the most solid of rocks. "I am aware of the sky, I am aware of that tree, I am aware of thinking, therefore I exist." You may be wrong about the words sky, tree or thinking but you are sure about being aware of something, about being aware. "I am aware, therefore I exist" or even more radically, "awareness is existence" or in simpler, more playful terms . . . "life is all you got". Even in day dreaming, thinking and sleeping you, are still aware, but light of awareness in mostly inside your head (day dreaming, thinking) or body (sleeping). Animals are calmly aware, in tune with their bodies and their instincts. 40 millennium man, however, is desperately trying to think his way out of his situation, fleeing his body, his instincts and the world. Eternal personal recurrence, bridged by the magic of death, shuts off the tyrannic, psychotic aspect of thought. You still think - it's a fun game and sometimes useful for finding food - but your vitality is elsewhere.
What might be more important to ask than a "proof" of the theory of eternal recurrence is . . . what is the value of this theory ? Is it a gateway to a "new health"? . . . . . My answer: It's the only "projection-mind-game" with the possibility of waking up, of happily and playfully dissolving itself to allow the possibility of localizing yourself in your immediate world, to allow what Fritz Perls so elegantly expressed as "losing your mind, and coming to your senses".
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