“Memory is never a precise duplicate of the original… it is a continuing act of creation,” researcher Rosalind Cartwright reminded us in her fascinating treatise on the science of dreams. “The biggest lie of human memory is that it feels true,” Jonah Lehrer wrote shortly before being engulfed in a maelstrom of escalating accusations of autoplagiarism and outright fabulation. Yet while we already know that memory is not a recording device, the exact extent of its fallibility eludes — often, quite conveniently — most of us.

In his recent New York Review of Books essay, legendary neurologist Oliver Sacks tackles precisely that, exposing the remarkable mechanisms by which we fabricate our memories, involuntarily blurring the line between the experienced and the assimilated:

It is startling to realize that some of our most cherished memories may never have happened — or may have happened to someone else. I suspect that many of my enthusiasms and impulses, which seem entirely my own, have arisen from others’ suggestions, which have powerfully influenced me, consciously or unconsciously, and then been forgotten.

One phenomenon Sacks argues is particularly common — if not adaptive — in the creative mind is that of autoplagiarism:

Sometimes these forgettings extend to autoplagiarism, where I find myself reproducing entire phrases or sentences as if new, and this may be compounded, sometimes, by a genuine forgetfulness. Looking back through my old notebooks, I find that many of the thoughts sketched in them are forgotten for years, and then revived and reworked as new. I suspect that such forgettings occur for everyone, and they may be especially common in those who write or paint or compose, for creativity may require such forgettings, in order that one’s memories and ideas can be born again and seen in new contexts and perspectives.

Citing a number of case studies where false memories of fictitious events were “implanted” in people’s minds, Sacks explores unconscious plagiarism, something Henry Miller poetically probed and Mark Twain eloquently, if unscientifically, addressed in his famous letter to Helen Keller. Sacks writes:

What is clear in all these cases — whether of imagined or real abuse in childhood, of genuine or experimentally implanted memories, of misled witnesses and brainwashed prisoners, of unconscious plagiarism, and of the false memories we probably all have based on misattribution or source confusion — is that, in the absence of outside confirmation, there is no easy way of distinguishing a genuine memory or inspiration, felt as such, from those that have been borrowed or suggested, between what the psychoanalyst Donald Spence calls ‘historical truth’ and ‘narrative truth.’ […] There is, it seems, no mechanism in the mind or the brain for ensuring the truth, or at least the veridical character, of our recollections. We have no direct access to historical truth, and what we feel or assert to be true (as Helen Keller was in a very good position to note) depends as much on our imagination as our senses. There is no way by which the events of the world can be directly transmitted or recorded in our brains; they are experienced and constructed in a highly subjective way, which is different in every individual to begin with, and differently reinterpreted or reexperienced whenever they are recollected. . . . Frequently, our only truth is narrative truth, the stories we tell each other, and ourselves—the stories we continually recategorize and refine. Such subjectivity is built into the very nature of memory, and follows from its basis and mechanisms in the human brain. The wonder is that aberrations of a gross sort are relatively rare, and that, for the most part, our memories are relatively solid and reliable.

Sacks concludes:

We, as human beings, are landed with memory systems that have fallibilities, frailties, and imperfections — but also great flexibility and creativity. Confusion over sources or indifference to them can be a paradoxical strength: if we could tag the sources of all our knowledge, we would be overwhelmed with often irrelevant information. Indifference to source allows us to assimilate what we read, what we are told, what others say and think and write and paint, as intensely and richly as if they were primary experiences. It allows us to see and hear with other eyes and ears, to enter into other minds, to assimilate the art and science and religion of the whole culture, to enter into and contribute to the common mind, the general commonwealth of knowledge. This sort of sharing and participation, this communion, would not be possible if all our knowledge, our memories, were tagged and identified, seen as private, exclusively ours. Memory is dialogic and arises not only from direct experience but from the intercourse of many minds.

In a rare act of defiant reliability, my own memory brought to mind a footnoted passage in Sacks’s mind-bendingly excellent recent book, Hallucinations, where he explores memory further:

We now know that memories are not fixed or frozen, like Proust’s jars of preserves in a larder, but are transformed, disassembled, reassembled, and recategorized with every act of recollection.

In a footnote, he adds:

For [researchers] in the early twentieth century, memories were imprints in the brain (as for Socrates they were analogous to impressions made in soft wax) — imprints that could be activated by the act of recollection. It was not until the crucial studies of Frederic Bartlett at Cambridge in the 1920s and 1930s that the classical view could be disputed. Whereas Ebbinghaus and other early investigators had studied rote memory — how many digits could be remembered, for instance — Bartlett presented his subjects with pictures or stories and accounts of what they had seen or heard were somewhat different (and sometimes quite transformed) on each re-remembering. These experiments convinced Bartlett to think in terms not of a static thing called ‘memory,’ but rather a dynamic process of ‘remembering.’ He wrote: Remembering is not the re-excitation of innumerable fixed, lifeless and fragmentary traces. It is an imaginative reconstruction, or construction, built out of the relation of our attitude towards a whole active mass of organized past reactions or experience. . . . It is thus hardly ever really exact.

Could it be, then, that the very fallibility of memory is essential to our combinatorial creativity and to the mechanics of the slot machine of ideation? To steal like an artist might be, after all, the default setting of the brain.

Oliver Sacks portrait by John Midgley via Wired