Esther and Mordechai writing the second letter of Purim. Oil on canvas, 1685. Photo: RISD Museum of Art, Rhode Island.

One of the most frightening aspects of old age is the potential onset of Alzheimer’s disease and dementia. Active, successful people slowly descend into a vacuum of helplessness, as their memory recedes and eventually fails them completely. Close family and friends become strangers, and the past — even the recent past — disappears into an abyss of emptiness. It is agonizing for those who go through it, and unbearable for those who love them. It seems that the only thing left is a shell — the personality that had characterized the Alzheimer’s sufferers throughout their lives is gone forever.

Or so we thought. Professor Susumu Tonegawa, a scientist from MIT, has discovered that Alzheimer’s patients’ memories may not be lost after all. Instead, sufferers have lost the brain mechanisms to retrieve them, even though they are still there. That being the case, the memories could theoretically be rescued by stimulating nerve cells to grow new connections. Well, believe it or not, this idea isn’t just a wacky theory — it has worked in practice, albeit only on mice.

In research on two different strains of mice, scientists at MIT used a technique called “optogenetics,” which uses light to activate cells that are tagged with a unique photo-sensitive protein. The mice with Alzheimer’s-like symptoms were stimulated with light and, incredibly, their lost memories of fear-invoking situations resumed, and when they were exposed to those conditions after the optogenetic treatment, the mice once again displayed a fear response.

The optogenetic treatment functions by helping neurons re-grow small buds called dendritic spines, which form synaptic connections with other brain cells. Currently there is no way for this technique to be used for human memory retrieval, but the success of this research creates realistic hopes for future therapies that will work in humans. As Professor Tonegawa put it: “The important point is, this a proof of concept . . . even if a memory seems to be gone, it is still there — it’s just a matter of how to retrieve it.”

There is a strange reference to memory in the Book of Esther. After the story of Purim is over, and the Jews have been victorious against the Haman-inspired genocide, the text instructs on how this miracle should be commemorated so that it will always be recalled: “These days should be remembered and observed in every generation, and the days of Purim will never vanish from among the Jews, and their memory will never be lost from among their descendants.” (Esther 9:28)

The Babylonian Talmud in tractate Megillah (7a) deliberates whether the Book of Esther was written with prophetic vision, and two of the rabbis base their affirmative view on the end of this exact verse, which seems to predict that Purim would remain a fixture of Jewish life forever. The Jerusalem Talmud, using this same verse, goes even further than its Babylonian counterpart, and suggests that other than the Torah itself, only the Book of Esther would endure as a sacred text among Jews up until the advent of Messianic redemption.

The problem is twofold. Firstly, why would Book of Esther even be considered as a contender for this enduring legacy, rather than any of the other books from Hebrew scriptures? Secondly, we ourselves are witness to wanton and widespread ignorance about Purim and the Book of Esther among contemporary Jews, no doubt all of them descendants of the Jews saved in ancient Persia who were included in the prophecy. So, was the prophecy wrong?

The Book of Esther, which records the origins of Purim, is biblically unique in that it is the only episode in ancient Jewish history that took place after the conquest of Canaan, but not in the Holy Land. It is a story of Jewish salvation and redemption on foreign soil and, even more curiously, the narrative is devoid of any reference to God or miracles. It is a story of the Jewish Diaspora, written about Jews who are in the midst of assimilation, and for Jews who might yet be affected by assimilation. The Book of Esther and Purim are there to remind us that there is a divine hand that guides our destiny, and although we may not be aware of it, that hand is always there in the background.

The Talmud is not suggesting that the Book of Esther and Purim will never be forgotten. Of course it will, and has been. Rather, the Talmud is telling us that the memory will never be lost; it just needs to be retrieved. With the right ontogenetic treatment, the connectors that succumbed to centuries of collective Alzheimer’s disease will reconnect every Jew to his roots, and to his identity. The powerful Purim narrative, with its echoes of countless other attempts to destroy us, can inspire every generation of Jews to believe that while we might be the Chosen People, that does not in any way mean that God intervenes directly and overtly every time we find ourselves in trouble.

The miracle is actually much more subtle. It is found in the fact that no attempt to annihilate Jews has ever succeeded, nor will any attempt succeed in the future. That is what makes the the Book of Esther a prophetic work. And that is exactly what we all have embedded on our hard drive, inerasable and for all time. So the fact that our enduring destiny is suppressed in many Jewish minds only means that those who are aware of it must work all the harder to find the suitable therapy that will reconnect as many Jews as possible to God through the memory of Purim, and through this important message of the Book of Esther.