Sherlock Holmes got Information overload right

I watched Sherlock the TV series before going through the books and since then, I’ve read/listened to many books in the series, but the first book ‘A Study in Scarlet’ has one idea in it which has stayed with me for quite some time and one which I still apply in my life.

The Scene

Almost at the beginning of the book, when Watson has first started sharing an apartment with Sherlock, he notes that his roommate has very peculiar habits. Sometimes he doesn’t talk for days; sometimes he stares at the ceiling for hours; sometimes he plays the violin melancholically and other times, he’s busy in his study.

But it’s too much for Watson when he learns that Sherlock doesn’t know about the Solar system. He doesn’t even know whether the sun goes around the earth or the earth goes around the sun and has no interest in learning about it.

And when Watson, after being violently surprised, explains what a solar system is, Sherlock says:

Sherlock: Now that I do know it, I shall do my best to forget it.

Watson could only say one thing about this “His ignorance was as remarkable as his knowledge”

Our brain is like an attic.

The explanation offered by Sherlock is pretty simple but profound:

Sherlock: ‘You see,’ he explained, ‘I consider that a man’s brain 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 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 most perfect order. It is a mistake to think that 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.

Your reaction to this must be very similar to Watson’s:

Watson: ‘But the Solar System!’

Sherlock: ‘What the deuce is it to me?’ he interrupted impatiently: ‘you say that we go round the sun. If we went round the moon it would not make a penny worth of difference to me or to my work.

Taking an analogy from computers where there are two types of memory which can be thought of as permanent memory (ROM/Hard disk) and working memory (RAM). Whatever function your computer is doing now, it stores that data in the working memory. Now, the working memory is fast but limited. So it becomes crucial only to put the things you need for it to function effectively.

You can always spend some more time and reference your permanent memory. But if you try to put everything in your working memory, ironically, there’s nothing in your working memory. Because now there’s no difference between the two. It’ll become slow and sluggish but will have all the data stored in it.

When you decide what’s important, you also decide what’s unimportant. By putting everything in your brain, you’re making a point that nothing is important.

Your brain can do wonderful things, but only if you give it space to do so. If you constantly provide it with useless information to store, it’ll store it, sure, but that’s the only thing it’ll do then. And our brains are supposed to be much more than a filing cabinet or a hard disk.

How does storing useless information in our brains affect us?

More information also leads to more noise because it increases the noise-to-signal ratio, which means that the more you know about something, the less you know about something. Some simulated research also implies that simply knowing more can make recognizing words, names and even letters harder.

Research also suggests that eliminating useless information from our brains is essential to learning and making new memories. And as we age, this lack of elimination affects our ability to learn effectively.

“If you only make synapses stronger and never get rid of the noise or less useful information, then it’s a problem,” said Tsien, the study’s corresponding author. While each neuron averages 3,000 synapses, the relentless onslaught of information and experiences necessitates some selective whittling.

Productivity often boils down to reducing the number of things that ask for your attention at a time. Every object, person, work, problem, and discomfort has a price. And that price is not the price tag attached to it but the amount of time and energy it takes from you. So, the more useless things there are around you, the poorer you are.

Eliminating trivial information and decisions becomes crucial to make your brain and, in turn, your life “richer”.

And if you look at the basics of increasing your productivity - removing distractions, multitasking, prioritization, deep work - everything is related to how you handle the information given to you digitally and physically. If you look at the information you deal with every day, the level of distractions/multitasking/prioritization depends on the volume and relevance of that information.

Although our brains can never be “full” in a way that they run out of space, it functions similarly to how Sherlock Holmes suggests that it’ll start elbowing out other information because our brain makes space available for new data by removing or ‘forgetting’ old data.

In the practical use of our intellect, forgetting is as important a function as remembering. - William James

Our brains then have an unlimited capacity to deal with new information, but this practice reduces or limits our working memory, which is critical for many domains of cognition, including planning, problem-solving and comprehension.

Applying the Sherlock Holmes principle in our lives

We get loads of inputs every day. A digital fire hose is on every one of us, all the time. This is all day, every day and then some more at our end-of-the-day scrolling session.

More data is created now every day than ever in history. A few minutes on any social media app will give you enough inputs and dopamine to make your brain resemble that of an amateur crack addict.

But one thing we’re amiss of when blindly scrolling through the feeds is that it’s our feed and though it might seem like we don’t have much control over it, it is in our control to allow or disallow something to enter our brains.

You are the gatekeeper of your inputs and, conversely, your life. The quality of thoughts and, ultimately, the quality of life you lead depends on how good a gatekeeper you are.

“How we spend our days is, of course, how we spend our lives.” - Annie Dillard

Don’t treat your brain like a hard disk.

Your brain is not a computer. Use tools to store information and your brain to connect and use that information. In the seminal book on productivity and time management, Getting Things Done, author David Allen says, “Your brain is great for having ideas, not for storing them.”

The Sherlock Holmes principle doesn’t just mean not storing useless information but also storing relevant information. We can apply the 80/20 law by only storing the top 20% of the information you come across in your brain and ignoring everything else. And surprisingly, that’s enough.

Of course, we think some information looks useless, but it might come in handy at some point in the future. We’ve all seen Slumdog Millionaire. Serendipity has its place, but using the cloak of serendipity to mindlessly collect information and think it’ll be useful one day is a big fallacy.

The purpose of the information is to transform it into knowledge that can entertain you or inform you. Bombarding your brain with too much information stops and forgets this process and soon starts to resemble a filing cabinet.

How to store information?

We are not computers (yet), so it’s not as mechanical to start uploading data in our brains in some particular way or following some rules of efficient data storage. But as with anything, the more you do it, the better you tend to get at it. So below are the laws/rules I try to follow when it comes to information:

  • Elimination is your friend. You may want to store that information, but you don’t need to. Have better filters in place.
  • Don’t be lazy with deciding whether or not you should store some data. Touch paper once. The information you put off until later is very expensive, time and energy-wise.
  • Apply the generation effect to all your information. Be more than a transcribing machine.
  • Don’t treat your brain like a hard disk. Use it like a processor. Leave space for it to think.
  • Go wide, store and read information about related concepts but don’t go too off-topic.
  • Great ideas are formed in the subconscious, slow-thinking brain. If you’re bombarding your brain, using your fast brain all the time and not letting your subconscious, slow brain work, you won’t be able to come up with ideas.
  • Take a walk.

Use tools. Don’t be the replacement for tools.

In 1997, a computer named Deep Blue defeated Garry Kasparov, then the world chess champion. Google’s AlphaZero AI program taught itself how to play chess and reached a superhuman level of play within 24 hours of training with itself.

In the book about AI Solomon’s Code written by Olaf Groth and Mark Nitzberg, Patrick Wolff, a former chess champion, discusses AlphaZero:

AlphaZero, for all its sheer computing and cognitive power, still lacked something innate to human grandmasters: a conceptual understanding of the game. AlphaZero can calculate at four orders of magnitude faster than any human, and it can use that power to generalize across a wide range of potential options across a chess or go board, but it can’t conceptualize a position or put it into language.

It’s almost 25 years since Deep Blue defeated Garry Kasparov. How has the chess practice of grandmasters changed since then?

These days, Wolff says, virtually every grandmaster will train with a computer, integrating it into their routine to help hone their game and develop new concepts—perhaps coming up with a more intricate opening or contemplating ways to counter novel tactics deployed by opponents.

By integrating computers into their practice routine, chess players have become way better, taking their game to new levels.

The motive of this post is not to debate AI and its future but to understand that whenever a new tool emerges, instead of replacing it or competing with it, we should think more about how to use it to our advantage.

Just like storing, searching, and archiving information can be done far better by computers than humans. Similarly, there are things that we humans can do that tools cannot.


Don’t ignore fiction. It also teaches you a thing or two sometimes.