Continuing our family tradition of reading physical, hardcopy books before bed, we started reading the original Sherlock Holmes stories by Sir Arthur Conan Doyle. Those were my favourite reads when I was growing up, and the one-volume collection of “all four novels and fifty-six adventure” was the first book that my wife and I bought for ourselves when we were graduate students. It took me some time to find this massive tome in the bookcase, and we started from the beginning – “A Study in Scarlet.”
Both my daughter and I enjoyed the description of how Dr. Watson got introduced to Sherlock Holmes’ extraordinary deductive abilities. There is one episode early in the book, though, where Holmes describes his approach to accumulating knowledge, with which I don’t completely agree (in my defence, neither does Dr. Watson, i.e., presumably, Doyle himself). There, Watson is astonished that Holmes didn’t know about the heliocentric model of the solar system, and that he was intent on forgetting it as soon as possible after learning about it. Here is how Holmes justified it:
” “You see,” he explained, “I consider that a man’s brain originally is like a little empty attic, and you have to stock it with such furniture as you choose. A fool takes in all the lumber of every sort that he comes across, so that the knowledge which might be useful to him gets crowded out, or at best is jumbled up with a lot of other things, so that he has a difficulty in laying his hands upon it. Now the skillful workman is very careful indeed as to what he takes into his brain-attic. He will have nothing but the tools which may help him in doing his work, but of these he has a large assortment, and all in the most perfect order. It is a mistake to think that that little room has elastic walls and can distend to any extent. Depend upon it there comes a time when for every addition of knowledge you forget something that you knew before. It is of the highest importance , therefore, not to have useless facts elbowing out the useful ones.” “
This is a compelling argument, but I suspect that the assumption about the rigidity of the boundaries of one’s brain-attic is wrong, particularly in the modern times. Perhaps, another, more up-to-date analogy is with the contents of the Photos app on a smartphone. Certainly, you could max out the memory if you take a ton of useless pictures and videos, but you can also upgrade your cloud storage or even the phone itself. And the AI-based search algorithms continually improve, to the point that the suggested compilations of “memories” rival those put together by humans. So the danger of not being able to retrieve useful information is not particularly great. Also, even without computer-augmented mental abilities, collecting broad information trains memory, if nothing else. Improved memory, in turn, increases our capacity to accumulate more information and, possibly, convert it to knowledge.
Incidentally, I’ve learned that Doyle himself was quite a bit more of a renaissance man than his most famous character, although even Holmes was an amateur violinist. In addition to being world-famous as a writer, Doyle had a successful medical carrier and was an accomplished athlete (footballer, golfer, boxer, skier and one of the first bodybuilding enthusiasts) and an amateur, but serious and successful, architect. I don’t think that this impressive lists of pursuits and accomplishments would have been possible if he had limited his interests and studies to medicine, which was his intended profession early on.
In defense of Sherlock Holmes’ approach, I think thatbeing selective about what to learn and what to ignore probably protected him from falling victim to the Dunning-Krueger effect. That’s a cognitive bias, where we overestimate or abilities due to limited competence in a particular domain. In other words, we often theorize or even act without knowing enough to even realize that we don’t know enough about what we are doing. For example, like me talking about cognitive psychology because of my interest in it but without any systematic knowledge of the field.
