In the late 19th century, Hermann Ebbinghaus conducted a pioneering experiment on himself, tracking how well he could memorize nonsense syllables. Based on the results, Ebbinghaus developed what he referred to as the forgetting curve, which is the rate that people forget information over time when they make no attempt to retain it. The sharpest decline in memory occurs within the first twenty minutes and continues to decline rapidly within the first hour. More recently, in his book “The Seven Sins of Memory: How the Mind Forgets and Remembers,” Professor Daniel Schacter codifies this forgetting that occurs with the passage of time as the first of his seven sins of memory that make us more likely to forget and labels it transience. One way to overcome transience, or the forgetting curve, is by spaced learning. By relearning the material after some time has elapsed, the rate of forgetting decreases.
The themes of remembering and forgetting recur throughout Parshat Ki Teitzei, perhaps most famously when we are commanded to “Remember what Amalek did to you on your journey, after you left Egypt… Do not forget!” (Devarim 25:17-19). What are the parameters and guidelines for fulling this commandment? How should we remember and how do we ensure not to forget?
In his explanation of this mitzvah, Rambam writes that it is a “positive commandment to constantly remember their evil deeds” (Hilchot Melachim 5:5). Notwithstanding the Rambam’s insertion of the concept of “constantly,” Sefer HaChinuch (Mitzvah 603) notes that there is no indication in the Torah or the Talmud as to how often one has to perform this commandment. Therefore, he suggests fulfilling the mitzvah every one to three years. Chatam Sofer suggests that the mitzvah must be fulfilled once a year because the Talmud indicates that memories generally last for twelve months (see Berachot 58a). While the exact details of how frequently we have to actively remember this mitzvah are debated, it is clear that if not for the spaced re-learning, transience will cause us to forget Amalek’s acts.
The second of Professor Schacter’s “Sins of Memory” is absentmindedness, or a lapse in attention that results in memory failure. We generally look at absentmindedness as something negative, as a “sin” that gets in the way of our goals. It is religiously and morally valuable to remember to perform worthy tasks, such as mitzvot, and to be mindful to avoid negative actions.
However, there is a commandment in Parshat Ki Teitzei that functions to redeem absentmindedness and forgetfulness—shichecha. The verse states that “[w]hen you reap the harvest in your field and overlook a sheaf in the field, do not turn back to get it; it shall go to the stranger, the fatherless, and the widow - in order that Hashem your God may bless you in all your undertakings.” (Devarim 24:19). Although in general overcoming failures of memory is essential for the religious personality, when it comes to overlooking meticulousness concerning one’s own possessions for the sake of benefiting others, absentmindedness and forgetfulness are valued.
May we merit learning how to properly use both remembering and forgetting in the service of God and others.