Book Summary: How To Think Like Sherlock – Improve Your Powers of Observation, Memory and Deduction

November 6, 2015

This is second post one in the series of Book Summary. I published summary of How to Win Friends and Influence People in earlier post. In this one, I’ll take Sherlock book on the grounds.

Repeating the common story:

” Since last year, I have developed this habit of creating notes while reading a book. Mostly, I read books on digital devices, either laptop or phone. Crunching the pages, I keep highlighting important passages I come across and then prepare well formatted note in Evernote. ”

On the same line, I read this book, How To Think Like Sherlock – Improve Your Powers of Observation, Memory and Deduction, made a comprehensive note, that summarizes the entire book in 9 pages. Sharing the summary here. Also, it’s available for download in pdf version.

Have fun!

A Little About The Book

This book will boost your powers of observation, memory, deduction and reasoning using the tricks and techniques of the world’s most famous detective.

It is packed full of case studies, tests and examples from the original novels.
Topics covered include:
* Mind Palaces
* Non-verbal tells
* Lie detection
* Intuition
* Concentration
* Listening
* Alertness
* Relaxation
* Logic
* Speed reading
* People watching
* Information shifting

and much much more…

You will never look at a shirt cuff, trouser hem or scuff on a shoe in the same way again!

From Goodreads

The Summary



You know a conjurer gets no credit when once he has explained his trick and if I show you too much of my method of working, you will come to the conclusion that I am a very ordinary individual after all.
A man should keep his little brain attic stocked with all the furniture that he is likely to use, and the rest he can put away in the lumber-room of his library, where he can get it if he wants it.

I : Preparing The Mind

Understanding Sherlock
Do you have the personality?
The truth is that many of the judgements we make about personality are instinctive and say as much about us as they do about the person we are judging.
Myers-Briggs Type Indicator (MBTI), a trademarked assessment first published in 1962 that categorises personality into one of sixteen types based on four dichotomies:
Extraversion (E) – Introversion (I)
Sensing (S) – Intuition (N)
Thinking (T) – Feeling (F)
Judging (J) – Perception (P)
Sherlock INTP/ISTP
Watson ISFJ
My ENTJ (Formerly INFJ)
Developing an Agile Mind
Being Alert to the World Around You

‘You see, but you do not observe. The distinction is clear.’

Seeing – that is, perceiving with the eyes – is easy; observation – absorbing into your brain the data provided by your eyes – is much more taxing.

‘The world is full of obvious things which nobody by any chance ever observes.’

If it is not a skill that comes easily to you, try consciously ‘observing’ in your daily life. If you’re on a bus or sitting in a café, look at those around you (while trying not to appear like a crazed, staring stalker!). The more you practise the skill, the more natural it will become.

Keeping an Ear to Ground
Just as important as developing your visual observation skills is improving your listening abilities.

As with improving your visual observation, the key to listening better is to consciously practise.

We listen in two ways: passively – when we listen to the radio, sit in a lecture or are walking down the street – and actively – for example, when we are participating in a dialogue.

There are a few simple exercises you can use to become a better listener. Tune in to the hourly news bulletin on the radio. Really focus in on what is being related. When the broadcast finishes, switch off the radio and jot down some notes about what was said. Can you remember each of the stories in the right order? And can you recall the broad subject or have you retained some serious detail from each? When you begin, you might be rather shocked by how little has soaked in. But if you keep up the practice for a while, you will likely see some striking improvement.

Similarly, sit in your garden on a summer’s afternoon. Close your eyes but keep your ears open. Note all the different sounds that you can hear, whether man-made or from nature. Such an exercise can help you become better attuned to the environment around you.

Improving your listening skills when you are part of a dialogue is a different challenge altogether. For the majority of us, when we converse we are more interested in being heard than hearing. But by being this way, we risk missing out on learning lots of new information that might prove very valuable to us.

Here are a few tips for improving your listening skills when in conversation: Don’t interrupt. Focus on speaker. Repeat it.
Reading between the Lines
Ability to fix his focus on the material most useful to the job in hand.
An average adult reading speed is somewhere between 175 and 350 words per minute. (Mine is approc. 400 wpm)
Read in an atmosphere conducive to concentration
Go somewhere quiet. Turn off the television, the radio, your telephone … anything that might distract you.Learn to chunk!
When we learn to read, we do so in a word-by-word form. However, we are capable of reading blocks of words.Learn to focus on key words
Stop sub-vocalizing
This means that a little voice in our heads says each word as we read it. A proficient reader really doesn’t need to do this. Your brain understands a word quicker than you can say it.
Keeping an Open Mind
We are so sure that we are right about so many things that the possibility we may actually be wrong about them is all but inconceivable to us.
Thinking Laterally

Simply put, an ability to think laterally – to look at a problem from many different angles rather than blundering into it head-on – can be a richly rewarding enterprise.

You might as well decide you can out-dribble Lionel Messi, talk about string theory more convincingly than Stephen Hawking, or wear something weirder than Lady Gaga. Some talents are bestowed on just a few, and when it comes to lateral thinking, no one touches Holmes.
Choosing Your Friends Wisely
Accepting Good Fortune

Richard Wiseman’s findings suggested that ‘lucky’ people generate their own good luck.

He wrote in the Daily Telegraph:

My research revealed that lucky people generate good fortune via four basic principles. They are skilled at creating and noticing chance opportunities, make lucky decisions by listening to their intuition, create self-fulfilling prophesies via positive expectations, and adopt a resilient attitude that transforms bad luck into good.
Ovid wrote, ‘Luck, affects everything; let your hook always be cast; in the stream where you least expect it, there will be a fish.’
In short, if good fortune chooses to search you out, do not reject it. Embrace it.
Learning from your Mistakes

But he knew that to make a mistake is forgivable so long as you make it only once.

‘Failure sucks, but instructs’

‘If you keep making the same mistakes again and again, you aren’t learning anything. If you keep making new and different mistakes, that means you are doing new things and learning new things.’
Keeping Focus

The best way to avoid making mistakes is to maintain concentration.

For most of us, our minds are in a state of flux. We keep a lot of stuff in our heads and too easily we can fall into the trap of turning it over to no real advantage. Without a bit of focus we might find ourselves utterly submerged beneath the chaos going on in our skulls. Yet somehow most of us maintain a degree of control over our thought processes by concentrating on whatever needs to be concentrated on at any given moment.

If you know that you need your concentration levels to be at their best, make sure you are eating and drinking well, getting a good night’s sleep and are incorporating some relaxation time into your schedule.

If you need a burst of concentration, a shot of caffeine might do the trick, though research suggests the more regularly you drink it, the less effective it becomes.

Keep things fresh. It is easy to slip into dull routine but boredom is a sure-fire way to lose focus.
Logic and Deduction

Accumulate evidence

Ask the right questions

Formulate hypothesis

Evaluate hypothesis

Form a conclusion

Like all other arts, the Science of Deduction and Analysis is one which can only be acquired by long and patient study, nor is life long enough to allow any mortal to attain the highest possible perfection in it. Before turning to those moral and mental aspects of the matter which present the greatest difficulties, let the inquirer begin by mastering more elementary problems.

Let him, on meeting a fellow-mortal, learn at a glance to distinguish the history of the man, and the trade or profession to which he belongs. Puerile as such an exercise may seem, it sharpens the faculties of observation, and teaches one where to look and what to look for. By a man’s fingernails, by his coat-sleeve, by his boots, by his trouser-knees, by the callosities of his forefinger and thumb, by his expression, by his shirtcuffs – by each of these things a man’s calling is plainly revealed.
Improving your Deductive Skills

‘It was easier to know it than to explain why I know it,’

Beware of the ‘conjunction fallacy’.

This is when two or more events that could happen together or separately are considered more likely to happen together than separately.

‘Linda is thirty-one years old, single, outspoken, and very bright. She majored in philosophy. As a student, she was deeply concerned with issues of discrimination and social justice, and also participated in anti-nuclear demonstrations.’

They then asked their respondents which was the more probable scenario:

1) Linda is a bank teller, or
2) Linda is a bank teller and is active in the feminist movement.
Eighty-five per cent of respondents went for the second option but by the laws of probability, the answer must be the first.
Kenny Adrenalin is discovered dead in the middle of the Sahara. He is face down in the sand, sporting a large backpack. There is no sign of foul play.
– He was jumping out of an aeroplane but his parachute failed to open.
Kenny’s brother, Benny, is found dead in the same spot a month later. He too is lying in the sand, naked, with a length of straw in his hand.
– Benny and some friends had hired a hot air balloon to inspect the scene of Kenny’s death. The balloon got into problems and started to lose height. The people on board threw any extraneous items overboard, including their clothes, in the hope of halting their plummet but to no avail. In the end they drew straws to see who would sacrifice themselves to save the others by leaping out and reducing the weight still further. Benny picked the short straw.

II : Building your Knowledge Base

Knowing your Subject
Holmes was focussed on the job at hand and he thus attempted to clear his mind of intellectual clutter irrelevant to a particular task. Knowledge for Holmes was purely utilitarian.

However closely you have read this book and feel you are prepared to follow in the Great Detective’s footsteps, do not insert yourself into a criminal investigation. Leave it to the police!

‘Google Effects on Memory: Cognitive Consequences of Having Information at Our Fingertips’.

Since the advent of search engines, we are reorganizing the way we remember things … Our brains rely on the internet for memory in much the same way they rely on the memory of a friend, family member or co-worker. We remember less through knowing information itself than by knowing where the information can be found.

What her study discovered was that we are far more likely to retain in our memories information that could not easily be found on the internet. However, where information could be retrieved from the web, respondents remembered how they could find that information again (e.g. through typing in a specific web address or search term) rather than the information itself. It is rather like remembering the name of a specific file within a particular filing cabinet, rather than the pertinent information within the file.

Reading the Signs
Albert Mehrabian, Professor Emeritus of Psychology at UCLA, argues that there are three major components in face-to-face communication: words, tone of voice and non-verbal communication. Of these, he rates verbal communication as the least important aspect (accounting for seven per cent of communication), then tone of voice (thirty-eight per cent) and, finally, body language (fifty-five per cent).

Sitting in a café for an hour and watching how the other customers interact with each other – the displays of affection, the temper tantrums, the seething resentments and complex power plays – can be a most instructive experience.

Different sides of the brain deal with different functions. In simplistic terms, the right side deals with emotions and creativity and the left with facts and memories. If you ask someone a question and they look to the right, this may be an indication that they are fabricating or guessing. Looking to the left is indicative of fact retrieval.

Direct eye contact implies honesty, interest and even attraction. Dilated pupils and widened eyes may also be a signal of attraction, while excessive blinking is suggestive of nervousness or excitement. Making ‘doe eyes’ by looking up and sideways (especially when done by a female) suggests both vulnerability and interest in a subject. Holding eye contact for an extended moment then looking away can be another signal of attraction.

Nervous ticks include nail-biting, trembling hands and activities such as fiddling with a pen.

Touching or scratching the nose while speaking is sometimes suggestive that the subject is lying.

Playing with hair can be a sign of flirtation or, conversely, a symptom of exasperation.

Leg direction while sitting. The feet and legs tend to point toward a subject of interest and away from one that is uninteresting or unwanted.

Laying your Cards on the Table

The aim of a great player is to perfect the ‘poker face’, that serene look which gives nothing away to the onlooker.

Watch the face
This is where a trained eye can spot ‘micro gestures’ that are hard to control. If the eyes smile, they probably have a good hand. Many pros wear hats and glasses to hide these micro signals.

Check out how a player stacks their chips
As a very broad rule, a player who keeps an untidy stack is likely to play a loose game. A neat stack suggests a more conservative player. Surreptitious glancing at their chips suggests an opponent is preparing an attack.

Leaning back into a chair in a relaxed but upright manner can indicate relief or confidence. Conversely, hunching forward can indicate nervousness. Some card players claim that a rapidly jiggling knee beneath the table is the surest sign that someone thinks they have a winning hand.

Mastering Disguise
Get the look
Work on expressions
Know your accents
Have a back story
Commit to the part
Breaking the Code

Cryptography (from the Greek for ‘hidden writing’) is the science of code- and cipher-creating, while cryptanalysis is concerned with breaking them.

In a code, each word or phrase is replaced by another word, phrase or symbol. Both the message sender and recipient must know what the coded words, phrases and symbols mean either by prior agreement or through use of tools such as code books. A code is a secret language.

In a cipher, each letter is either replaced by an alternative letter, number or symbol (a substitution cipher) or the letters are shuffled about (a transposition cipher). Plaintext is the name given to the information you wish to communicate, while ciphertext is what is actually sent.

The Caesar cipher
The transposition code
Pig Latin
The pigpen cipher
Jargon code
Morse Code

One of the greatest weapons in the arsenal of the cryptanalyst is ‘frequency analysis’. This relies on the fact that in almost all languages, certain letters are used more frequently than others.

Information Sifting
Have control over your data
Keep an eye on the bigger picture
Give yourself time and space to evaluate the information
Don’t be over-reliant on intuition
Beware the ‘recency’ effect
Retain the chaff

The secret to good notes, as any exasperated university lecturer will tell you, is not to take down verbatim accounts. Such an approach ensures that data will slip seamlessly in and immediately out of your brain. The trick is to actively engage with the material you are taking notes on, encode it in a way meaningful to you and reference it to your own knowledge.

One popular way to visually present interconnected ideas or subject matter is the spidergram, also known as the mind map. Spidergrams are a great and simple way to concentrate a lot of ideas in a small space, making review easy and often prompting new trains of thoughts by giving you an overview of the big picture.

Improving your Memory
Sensory memory
Short-term memory
Long-term memory

External aids are fine for filling certain gaps but there are disadvantages to becoming over-reliant upon them. While there is no problem in using an alarm clock day in and day out to remind us to get up, we might not want to rely on writing too many reminder notes to ourselves simply because it becomes inconvenient. Many studies also suggest that an over-reliance on external aids can make our memories lazier and less able to function without them.

Internal aids are certainly the way forward when it comes to improving our all-important long-term memory. Here are a few techniques you might want to try:

Make it personal
Use imagery
Say it loud
Remember just as you are about to forget
Implementation intentions -If you need to remember to do something on a regular basis, then this might work for you. It is a system of self-regulation so that you might tell yourself, ‘I must take my pills with my cup of tea just before bedtime’.

Archie is the getaway driver for a gang of robbers who plan to rob a local post office. They enter the shop at quarter to six in the evening and hold up the staff as they are cashing up for the day. The robbers have told Archie to have the motor running and ready to go at six o’clock precisely. Sure enough, from his driver’s seat, Archie watches the gang enter the post office at a quarter to six. Ten minutes later, he looks at the clock on the dashboard and sees that it is five to six. A minute later it says, as expected, four minutes to six. But when he looks again two minutes later, it still says four minutes to six. ‘The time sure drags when you’re tense,’ he thinks to himself. A minute later he looks at the clock again. Now it says the time is five to six. Utterly bewildered, he starts to panic. Is time really going backwards? Is he losing his mind? A minute later, he looks once more at the clock, realises he is actually quite sane and hurriedly powers up the engine as the gang emerge from the post office, swag-bags in hand. What was happening to time?

– The clock on the dashboard was digital, and the top-right vertical stroke of the last digit was not working.
Taking a Walk Down Memory Lane
Reaching Conclusions
Be in the right frame of mind
Gather your raw information
Evaluate the data
Be a reader of human nature
Search for anamoly
Think the unthinkable
Formulate hypothesis
Don’t mistake correlation for causation
Be rigorous
Exclude the impossible

Now, to paraphrase the Great Detective, you now know his methods. Use them!

 More on same line:

  1. Reply


    August 9, 2016

    Dont come more in common interests . Enough is enough

    • Reply

      Darpan Dodiya

      August 9, 2016

      Hahahah! Facts remain facts. 😛

  2. Reply


    July 4, 2016

    Ahaan !!
    Matches lots of interests of your topics and my interests 🙂

    • Reply

      Darpan Dodiya

      July 5, 2016


      Happy Sherlocking! 😛


Darpan Dodiya
Raleigh, NC, USA

Hi! I'm Darpan. 24 yr old Software Engineer, now pursuing Masters in Computer Science at NC State University, USA. This is my personal blog to share my interests in travelling, photography, programming and life. Glad to see you here, have a look around the website, you'll enjoy. Drop a comment or reach out to me or get connected via links below. Have a good day! :)