Between Mnemosyne and Cassandra

“There is no greater sorrow than to be mindful of the happy time in misery.”

Dante Alighieri, Inferno (Canto V)

“The stream of Lethe issues from your kisses And powerful oblivion from your lips.”

Charles Baudelaire, The Flowers of Evil (Lethe)

If given the chance, would you choose to remove painful memories at will? If given the choice, would you rather keep the lesson and discard the episode attached to a painful memory?

I call mnemoalgia the pain that comes with remembering. Anyone who has gone through a heartbreak, a traumatic experience or the loss of a loved one knows that memory can hurt. And at times we would prefer to have the capacity to switch off or even completely remove memories that don’t allow us to function normally on everyday life. We have developed different psychological techniques to override or to tame the miraculous memory system (or systems) that we possess, but it looks like we could also benefit from cultivating a little bit more the capacity to forget.

A lot of melancholy stems from our minds wandering in the past, and a lot of anxiety stems from them wandering in the future. Mnemosyne was the Greek goddess of memory and mother of the nine muses. She was the goddess, whom ancient Greeks would summon when appealing to a big feat of memory. Thus, her abode was the past. On the other hand, Cassandra was a Trojan princess, daughter of Priam, the king who suffered the Greek invasion of Troy. She was cursed by the god Apollo for rejecting his sexual approaches. The curse consisted in being able to foretell the future without anyone believing her prophecies. And as in any Greek tragedy, Cassandra predicts the Greek invasion and the appearance of the Trojan horse, but no one would believe her; therefore, she was unable to prevent the demise of Troy.

Our minds go from Mnemosyne to Cassandra, and back. They oscillate between past and future, between memory and speculation, and at times this oscillation results in mental distress. We would be better off if we could remain in the present. Actually, it takes some training to focus our attention on it, and to prevent our focus from flying to either direction. “Thinking a lot” seems more like a symptom of the weak mind, rather than a true mental feat. We would be calmer if we exercised two different skills, namely, to be able to stay in the present and to forget a particular memory. In this regard, let’s remember the work of the medieval natural philosopher Giordano Bruno, who worked extensively in the art of memory in order to develop techniques to improve memory and recall. Let’s imagine an inverse Giordano Bruno who instead of devoting his studies to memory, devoted them to oblivion and the development of techniques to selectively erase memories. Wouldn’t that be as useful as exercising memory?

In fact, there was a goddess devoted to forgetfulness in the Greek pantheon from whom we barely hear about. Her name was Lemosyne, or Lethe for short. Her presence in the Greek pantheon suggests that forgetfulness had a special role in ordinary life. Moreover, Lethe is the name of a river in the underworld of Greek mythology. According to the myth, the souls who drank from its waters would forget their previous life. Possibly, a requirement for eternal peace.

The past is gone, and the memories that we might have of it possess a reliability that decays with time. The future is non existent, and any forecast we do of it should be taken cautiously, and with some amount of skepticism. Why then does the mind like wandering between these two unreliable places? Our minds naturally tend to go from one extreme to the other. It seems that thinking about the past and the future implied an evolutionary advantage to our ancestors.

Well, we do not need to look too far in order to see all the advantages of a brain that is able to speculate and hypothesize about the future. A requirement to do so, is to possess a memory system. Ours is a successful species because our minds are capable of putting two plus two together, to link effect to cause with some degree of accuracy. That is the essence of learning, and that we have in common with other species which are susceptible of being trained. These do so because they are able to link their inner representations of events with the reception of rewards or punishments.

Memory is essential for learning. These two, memory and learning, are so tightly related that one could argue that they are one and the same thing: to learn implies the existence of memory and vice versa, to memorize implies learning. The ruminating process that takes place, for instance when we feel we did something wrong, is the mind (the brain) replaying the events that led to the negative outcome in order to find which was the particular event that led to the negative outcome. This rumination also occurs in positive or neutral events. For instance, it sometimes happens to me that when I just met a person, their impression in the form of visual stimuli, tone of voice and even smell is repeated in my mind for a period of time when the person is gone. This is the feeling of the process of memorizing or learning the person I just met.

Modern neuroscience divides memory in explicit and implicit memory depending whether its consolidation implies conscious thought or not, respectively. Explicit memory is further divided in semantic and episodic memory. As the name of the latter suggest, this refers to the memories that possess a spatiotemporal quality to them, which means that they are remembered as an episode comprising most of the time sequences of visual and auditory stimuli, or rather, representations; whereas semantic memory lacks this quality and refers to knowledge acquired by the mediation of language. For instance, the knowledge of Paris as the capital of France falls in this category. Lastly, implicit memory comprises unconscious storage and recollection of information. Knowing how to ride a bicycle would fall in this category.

Coming back to the question at the beginning of this essay, wouldn’t it be good if our memory systems kept only the outcome of an event, rather than the whole episode? Or in other words, wouldn’t it be better to keep only the lesson rather than the whole episode? Or why is it that the mind needs to preserve more than it should?

We are the descendants of successful apes that emerged in Africa thousands of years ago. Episodic memory probably implied a great evolutionary advantage in comparison to those individuals who didn’t. Keeping a whole episode in memory probably allowed for later recollection to extract or deduce information that initially was not considered.

It has also been shown in patients with memory deficits, that their capacity to imagine and think about the future is also impaired. This suggests that memory plays an important part of projecting into the future. This is only natural as memory provides the raw material for imagination. If we didn’t have stored concepts, knowledge or experiences, then what would we speculate about? Cassandra and Mnemosyne are very strongly related, it seems.

And thus, episodic memory possibly entailed a great evolutionary advantage to early humans not only by allowing ulterior extraction of meaningful knowledge but also as a capacity to think about the future, to imagine, plot and speculate. Capabilities that are required for optimal decision making and planning.

As important as memory seems in our life, either to think about the past or to think about the future, the capacities to keep our feet in the present and to forget memories as voluntary as possible are of vital importance. These might be essential ingredients to live a peaceful life, and thus, the goddess Lethe should have an important role in our lives as those of Mnemosyne and Cassandra.