Our Gemara on Amud Aleph quotes a proof text regarding prohibitions of eating a limb taken from a live animal (Devarim 12:23):

“But make sure that you do not partake of the blood; for the blood is the life (of a soul), and you must not consume the life (soul) with the flesh.”

There is a mystical interpretation to this verse, read more literally. The Hebrew word used for life is nefesh, which also means soul. From a kabbalistic point of view, some persons’ sins are so severe that they are reincarnated as beasts. Therefore, to improperly use the meat, by not slaughtering it, and especially cruelly disposing of it, can be hurting a human soul too, and not just an animal. (See Nishmas Chaim IV:13, Shalah, Torah Shebiksav, R’eh, Torah Ohr and Shevet Musar 14.)

The idea of reincarnation seems out of our experience and not relevant to us. In one sense that’s true, as it does not have anything to do with core Torah principles of faith, and indeed it is not a universally held belief. For example, see Sefer Ikkarim (4:29) and Rav Saadiah Emunos V’deos (6:8). Yet, the idea that what we do not resolve or repair will haunt us, not just in life but even in death, feels compelling. It is because in some sense we realize that we carry within us the unresolved psychological and emotional concerns of our ancestors.

Psychologically speaking, this is known as a legacy burden. I myself am not a direct child of a survivor, though my mother was deeply affected by the war, hiding out in England, fearful of the V2 rockets raining down hell and destruction. Yet, at weird times I feel it in my bones. When I go through security and they ask for my ID, I hear a Germanic sneer, “Papiere?” When I see the ubiquitous traffic cameras all over, all I can think is how easily that can be retooled with a few keystrokes into an oppressive tool of a totalitarian regime enacting lockdowns for “our own protection.” (Oh wait, that actually DID happen and it was not a COVID fever dream. Why has no political party sincerely and systematically reflected on or reviewed the civil rights atrocities of those recent dark years? We are all embarrassed and ashamed and want to forget it happened. But it did happen, and without proper reflection and judicial reforms we are in danger of it or worse happening again. What happens if one ethnic group (Jews?) is identified as more susceptible or more likely to be carriers? Imagine combining the hysteria of COVID with the hysteria of antisemitism! But I digress…)

In psychological development, there is an unconscious tendency to repeat and recreate disturbances and dysfunctions in our current relationships that correspond to past and primary relationships. This is known as the repetition compulsion, and it represents an unconscious effort to revisit and rectify past pains, although it often leads to people recreating their fathers in their bosses or siblings in their co-workers and problematic attachments in their romantic life. This is why the idea of reincarnation, whether actually true, metaphorically true, or both, is more relevant than one might think. In the end, we have an urge to revisit our failures until we can turn them into successes.

So modern man may consider reincarnation to be foolish superstition, but you cannot outsmart human nature. Call it what you want, we are in danger of repeating old patterns until we rectify them.