Archive for the 'Deduction' Category

Art of Deduction Review

Thank you to the Doc:

Review written by John H. Watson

Twitter:  @JohnHWatsonMD

About the Book

Most of the books that I chose, or am asked to review, are pastiches or books by authors who have studied the many adventures Holmes and I had together. Recently there have been a few books looking at specific aspects of Holmes’ ability as the first consulting detective.

The most recent of these is entitled “The Art of Deduction” by Taz Rai and is a detailed analysis of Holmes methods against several well-known text books on logic and deduction.

It is a very well-researched book which quotes frequently and accurately from my stories to present the key skills that anyone wishing to emulate the Great Detective will need to master.


Rai tells me that in writing the book he began to realise the possibilities if the average person could acquire even a modicum of the skill possessed by Holmes. In many of our adventures together the most complicated problem turns out in the end to have an absurdly simple solution. Rai suggests that we can all learn from Holmes and that with the application of a little logic, rationality and observation, we can solve problems in our own lives without resorting to help from others.

Rai wondered as he read my reminiscences if it was possible to deduce and learn to think the way Holmes does. This triggered the idea of writing The Art of Deduction. He read all my stories again plus several books on logic and philosophy. He also conducted a survey to see what Holmes fans wanted and the result is the four parts that comprise his book.

He suggests that although everyone has a vague notion of logic, by reading my stories about Holmes cases, you can begin to understand what its benefits are. He believes it is important to read and understand logic and how Holmes uses logic in his work. If Holmes is thought of as a superhero then his superpower is logic, Rai suggests. He also believes that because we can relate to Holmes as being human also it is  possible for us to attain some measure of his amazing gift. Many exercise in the gym to build muscles, lose weight, etc. and he suggests that the same approach can be applied with logic and deduction in the mind. Holmes is an example of what one can acquire, but to get there is not necessarily understood.

The book is in four parts.

Part One – A Study in Sherlock

The many facets of the personality of Holmes are analysed including the rationality of his approach to a case eschewing emotion, superstition, irrationality, and fallacies. His use of evidence, the scientific method and the acquisition of useful knowledge is discussed. We then look at his methods of abstraction and distraction, his immersion in lengthy chemical experiments, and then his intense concentration. Finally his vices.

The section draws on A Study in Scarlet, The Sign of Four, The Hound of the Baskervilles, The Abbey Grange, The Copper Beeches, The Norwood Builder, Silver Blaze, The Valley of Fear, The Boscombe Valley Mystery, The Mazarin Stone, The Man with the Twisted Lip and The Yellow Face.

Part Two – A Case in Logic

This looks at the science of logic and Rai suggests that if you read these pages you will be able to infer the possibility of a Niagara or an Atlantic from the knowledge of a single drop of water (as Holmes suggests in A Study in Scarlet). The heading of the one of the sections in Part One – Five Pillows and an Ounce of Shag – would be an appropriate setting for reading this section.

Again Rai draws heavily on the Canon to illustrate the application of logic including A Study in Scarlet, A Scandal in Bohemia, The Copper Beeches, The Yellow Face, The Sign of Four, Silver Blaze, The Norwood Builder, The Boscombe Valley Mystery and His Last Bow.

If you have ever wondered what the difference is between deduction and induction, what categorical propositions, categorical syllogisms, disjunctive syllogisms and the inductive force are then this section should make it all clear!

Part Three – The Observation Ritual

You see but you do not observe must be Holmes most common admonition, of me at least. This section deals with the need for acute and meticulous observation of detail. This is about turning the familiar saying about not being able to see the wood for the trees on its head and carefully observing the trees, branches and leaves before jumping to conclusions about the wood.

In this section he draws on The Norwood Builder, The Blue Carbuncle, The Stockbroker’s Clerk, The Hound of the Baskervilles, The Reigate Squire, The Sign of Four, The Golden Pince-Nez, The Dancing Men, The Resident Patient, The Valley of Fear, The Speckled Band, The Yellow Face, and of course, A Study in Scarlet, with the unforgettable “You have been in Afganistan, I perceive”.

Part Four – The Sign of Holmesian Deduction

This section takes two of our cases – The Beryl Coronet and The Musgrave Ritual – and looks at how Holmes brings all his skills to bear on a particular problem.

As with most of our adventures, they follow a common pattern. The client arrives at states the nature of the case. Then there is the initial analysis of the problem from the facts known at that point. This indicates the need for further investigation before the denouement.

Epilogue – Real World Application

The final section gives us a real world example and takes us through the same stages as in Part Four.

In Summary

Even after many years working alongside Holmes on innumerable cases, I still struggle to apply his methods and get the results he can so easily obtain. Perhaps this is a question of innate ability coupled with intense practice. He has dedicated his whole life to it and perhaps that is what gives him the edge.

Nevertheless, this book is a very thorough analysis and maybe, just maybe, the application of the principles as Rai has laid them out may make it possible to emulate Holmes. I would be interested to hear from anyone who gives it a go and achieved some measure of success.

Finally, as you can see from the cases that are listed above (and I may have missed some), the book draws on many of our cases and it may be instructive to pick out those that Rai calls on more than others and read those ones alongside Rai’s book.

About the Author

Taz Rai is a young Business Graduate living in Australia who has given up his day job to focus on his love of writing and on someone he clearly admires. He first read about Holmes when growing up as a child and Holmes’ logical approach appealed to him. He says he doesn’t have a favourite story (his book is full of examples from all over the Canon) as he says each story showcased something new about the character of Holmes.

His favourite Holmes and Watson portrayals are,  predictably in these modern times , Benedict Cumberbatch and Martin Freeman. Their portrayals, particularly Cumberbatch’s thinking or maybe I should say deducing machine, must serve to illustrate how difficult in practice, even with the aid of this book, it would be to emulate Holmes.

Posted on Mar. 19th 2012 11:08 AM | by MagicRai | in Deduction, General, Logic | 4 Comments »

Holmesian Deduction

Anyone who has read Arthur Conan Doyle’s Sherlock Holmes stories will be aware and probably in awe of his deductive and logical prowess. In the stories, it reads like something of a super-power, and many people wish or even fantasize about attaining similar skills themselves. Holmes’ talents frequently leave the other characters dumbfounded, and in “The Adventure of the Devil’s Foot” Dr. Leon Sterndale even denounces Holmes as “the devil himself.” This allegation is unfounded, and throughout the stories, we (along with Watson- essentially Holmes’ student) learn that his methods are firmly rooted in the study of logic.
Deductive arguments are one of the two major argument forms covered in the study of logic. A deduction is essentially a conclusion that is drawn from a series of premises. For example, from the facts that “Sherlock Holmes is a great detective” and “great detectives are experts in deduction,” we could deductively infer that “Sherlock Holmes is an expert in deduction.” This is a deductive argument because if the two premises are true, then the conclusion has to be true. The other type of argument is an inductive argument, where the premises provide good grounds for accepting a conclusion, but do not prove it beyond all doubt.
Sherlock Holmes is able to take this basic skill and make it into something spectacular. How he does this is by employing a mixture of deductive and inductive reasoning (which he refers to as “the balance of probability”) to reach a reasonable solution to a problem. Forming deductions in the way Holmes does is the process of deciding what can be reasonable extracted from a given set of facts.
To employ this skill in your life, you first have to think rationally. Imagine that several boxes of stock have disappeared from a shop. Matt, Sarah and Harry are suspects. Matt was fired from his last job for theft, but Sarah and Harry are the only staff members that have keys to the store-room. Matt and Sarah were both working on the day of the disappearance.
From this situation, it is tempting to suspect Matt. He has been in trouble for this precise thing before, and he was working on the day of the theft. You couldn’t, however, validly infer that this is true, because he doesn’t have the means to get into the store-room. For Matt to be guilty there would have to be an explanation of how he got in. To a rational mind, schooled in deductive reasoning, Sarah and Harry are more likely suspects.
Holmes knows you can only reason correctly from evidence, and likewise, when you make your own deductions, you have to focus on proof. In this example, you would search diligently for any further evidence, and then see if your theory still holds up. Deduction isn’t a super-power; it is an attainable skill, if you look to the master.

Posted on Jan. 30th 2012 7:26 PM | by MagicRai | in Deduction, The Art of Observation | 11 Comments »

Sherlock and Rationality in Modern Times

In July 2010, Mark Gatiss and Steven Moffat’s spectacular new television series, Sherlock, aired in the UK.  The three 90-minute episodes gave the public a much needed reminder of why Arthur Conan Doyle’s stories are so timeless, and why his greatest character is still a hero in modern times.

Benedict Cumberbatch takes up the legendary role, with Martin Freeman in tow as Dr. Watson, and the pair are thrust into 21st century London, taking up their residence at 221B Baker Street.  Holmes is infused with his usual intelligence, charm and charisma, and makes his deductions with characteristic ease.  The series truly brings to light how rationality and logic are still valid today, and shows how elements of Holmes’ character can be of a benefit in the modern world.
Rationality, as Holmes displays throughout the classic stories and modern episodes, is much misunderstood in today’s world.  Holmes himself comments in “A Study in Pink” (the first episode of the BBC series, a play on the title of the first Holmes story A Study in Scarlet), “I am not a psychopath, Anderson, I am a high-functioning sociopath.” This perception of the rational mind as cold, unemotional, and therefore somehow evil pervades into modern times, perhaps left over from society’s deeply irrational past (even in Holmes’ time, brandy was used as something of an all-purpose cure by medical professionals).  The truth, as Sherlock so elegantly reminds us, is that a rational mind, undeterred by emotional consequences and well-schooled in deductive reasoning, can accomplish a lot.
The sad truth is that in the modern world the general public’s irrationality is often manipulated.  Whether it is a completely unjustified scare-story in a newspaper, politicians making unfeasible promises or pseudo-scientists trying to sell you homeopathic cures, people are trying to exploit you all the time.  Sherlock Holmes, thanks to his mercilessly rational mind, is able to see through mystery as if it wasn’t there.  His careful unpicking of the cipher in “The Blind Banker” (the second episode of the TV series, based loosely on the Doyle story “The Adventure of the Dancing Men”) serves as a perfect analogy.  There are coded messages coming at you all the time, and just like Holmes, you have to make your own sense of them, and see the truth behind the mystery.
Holmes makes these skills seem fantastical, but the truth is they are absolutely attainable.  Rationality is as easy as asking questions, and thinking in terms of evidence, rather than conjecture.  The original Holmes stories are beautifully-aged gifts to the student of rationality, and Sherlock presents them in a modern and humorous package.  For more information about Sherlock Holmes and rationality, see Taz Rai’s eBook, The Art of Deduction.

Posted on Jan. 10th 2012 9:28 PM | by MagicRai | in Deduction, General, Logic | 1 Comment »

My Superpowers are….Elementary

Sherlock Holmes is like a superhero.  He may not be ordained with traditional superpowers like the classic heroes such as Superman and Spiderman, but he uses his abilities to set himself apart from the herd.  Uncle Ben’s immortal words to Peter Parker, “with great power comes great responsibility” ring true when viewed in respect to Holmes.  His power is all intellectual, and he has fostered an immense practical knowledge in order to be able to use his powers for the greater good.  The loving narration of his “side-kick,” Watson, both revels in Holmes’ astounding displays of talent and accepts that once his process has been explained, it seems very simple indeed.
The main difference between Holmes and most superheroes is that his skills are attainable to dedicated students.  Not only that: the wider aspects of thought which back up Holmes’ abilities are useful to people throughout their everyday lives.  Being able to look at advertisements, political campaigns and the claims of other self-promoting charlatans with a critical and rational eye is a non-superpower that is just as valuable today as it was in Holmes’ day.
Unfortunately, for those of us who wish to acquire similar skills to Holmes, we can’t just pray that we are really alien orphans or attempt to get bitten by a radioactive spider.  Developing intellectual powers similar to Arthur Conan Doyle’s masterful hero takes time, and you must train diligently, like an aspiring Bruce Wayne, rather than being automatically catapulted to greatness like Peter Parker or Clark Kent.
Despite all the difficulties in achieving similar skills to Holmes in logic, observation and deduction, taking lessons from the great detective can be of benefit to people from all walks of life.  Puzzles come in many forms, and it would be hard to find a person who didn’t wish to be able to more efficiently solve them.  These puzzles pervade into our existence as people try to hide things from us, or confusing and unexplainable situations arise.  With the skills of Holmes under your belt, you can cut through the fabric of mystery with your laser-vision, and navigate the webs of lies placed before you, constructing the truth along the way.
The need for these skills is prevalent throughout everybody’s lives, and the struggle to unveil deception seems inexorably linked to the instinct for survival.  You need to know when your employer isn’t quite what he seems or when the truth is being shielded from you in order to succeed in life.  People who allow themselves to be blindly led along lose in the Darwinian race.
Holmes’ literal and specific application of his talents may be mainly of interest to detectives and medical professionals, but the underlying ideas are valuable across professions.  Holmes teaches us to question our own assumptions, rely on evidence rather than conjecture, and to think in logical terms.  These skills combined can lead to greatness, and all advances in medicine and general thought are dependent upon rational appraisals of the subject matter.  In a way, the skills Holmes uses in solving the mysteries that are posed to him are the same skills the world needs from their doctors, scientists, and leaders in the future.
It is with this in mind that “The Art of Deduction” has been written.  It is a gift to the Sherlock Holmes fans of the world, and shows what anybody can accomplish if they apply Holmes’ skills in life.  The eBook focuses on the underlying ideas, skills and techniques that are used by Holmes in his cases, and is a guide for anybody who wishes to attain similar skills themselves.  The raw skills are described in detail, and through a detailed analysis of the original Sherlock Holmes stories and novels, you can learn how to use Holmes’ mental superpowers in your chosen field.  Luckily, there isn’t an equivalent to kryptonite that works on rationality and logic; once the skills have been learnt they will be beneficial to you for the remainder of your life.  The Sherlock Holmes stories are a series of excellently framed lessons in rationality and logical thinking, and “The Art of Deduction” compiles those lessons into a concise guide.

Posted on Jan. 3rd 2012 12:18 AM | by MagicRai | in Deduction, General | 6 Comments »