Reincarnation is a complicated topic because we most often have great difficulty expressing just what we mean by the term. Because, if it is really “me” who is reborn in such a case, would this not mean that I would have to be able to recall my previous existence? On the other hand, however, we have no doubt that, in the case where we should develop grave senile dementia, it would still be “we ourselves” and no one else who would continue to exist, even though we would no longer be able to remember anything. If we were able here and now to take certain measures which would bring it about that in such a condition of senile dementia we would not have also to suffer certain further pains, we would, it must be supposed, indeed take such measures; we would not say: what happens to me some decades from now is a matter of indifference, if the “I” that exists then will have no memory and will, consequently, be a different person from me. This phenomenon of grave senile dementia is clear evidence that our continued existence is not necessarily linked to the ability to remember. With a little imagination, then, one can envisage how a “second existence” (after one or another form of reincarnation or rebirth) might likewise not necessarily have to involve any memory of the past. For this reason, it would seem not to be entirely unreasonable to try to develop a “reincarnation test” for the purpose of testing nativistic theses and beliefs.
Eduard von Hartmann (1842–1906)
One interesting model for such a “reincarnation test” was developed by Eduard von Hartmann in his “Philosophy of the Unconscious”. This involved taking away all his memories from the test subject, without said subject ceasing thereby to be himself (a phenomenon which we do indeed encounter in the most serious cases of senile dementia):
“Imagine a man who, though no genius, is nonetheless a man of up-to-date general culture, equipped with all the material goods of someone in an enviable social position, in the prime of life, and fully aware of the advantages he enjoys over the members of the lower classes, the inhabitants of more primitive nations, and the subjects of more savage times, and who in no way envies the man placed above him who is tormented by all the discomforts that he himself has been spared – a man, in short, who has neither been worn out and made blasé by excessive pleasures nor been oppressed by any especially heavy blows of fate.
Now imagine Death stepping up to this man and speaking as follows: “The time allotted to you has run out and in this very hour you shall fall prey to annihilation. But it is up to you to decide in this moment whether or not, after completely forgetting all that has hitherto transpired, you live through once again, in exactly the same way, this life of yours which is just now coming to an end. Now choose!”
I doubt that the man in question will prefer, to non-being, this repetition of all that has already played out once before – assuming that he considers the matter quietly and without intimidation and that he has not lived his life in a way so lacking in thought or reflection that, unable to perform any brief critique of his own life-experiences, his answer will give expression only to the will to live at any price or his judgment will be entirely distorted thereby. How much more, then, would this man have to prefer simple non-being to a re-entry into a life which would not guarantee to him those favourable conditions that his former life had and which would, on the contrary, leave it entirely up to chance what new conditions of life he might find himself entering into – that is to say, would, with a probability verging on certainty, provide him only with worse life-conditions than those that he had just scorned.
But the unconscious would itself be in the same position as this man at every moment of a new birth, assuming it really had the possibility of making such a choice.” (Eduard v. Hartmann, Philosophie des Unbewussten)
Even a generally contented man, Hartmann supposes, would not cherish the wish to be reborn in the sense of having, after having forgotten his past life, to live this life through once again. All the more, then, would a contented man decline to accept his own rebirth under altered conditions: namely, if it were left up to chance (>the Lottery) or to the unconscious just which social or biological condition he would be reborn in. Against the background of the necessity that ethical principles be universalizable we must now ask: if I decline to accept that in my own case my life should be lived through again – let alone that the journey through life should be made anew under biological and social conditions that remain unknown to me – how I can reasonably impose such a life-journey on someone else by begetting him and surrendering him up to the unknown? Were that “unconscious” (which in Hartmann’s philosophy is blind) endowed with foresight, it would flinch back in horror from every such begetting. We ourselves, however, do possess such foresight, for which reason – and this is the logical antinatalist conclusion of Hartmann’s own exposition, a conclusion he does not share – we should not act in such a way that new human beings begin to exist.