Book Review: The Math Instinct by Keith Devlin

Problem: 243 minus 75

Solution: You just give me the two hundred. I’ll give you twenty five back. Plus the forty three you have, the hundred and forty three, that’s one hundred and sixty eight.

Q a complicated algorithm for a simple computation huh. but interestingly, this is how brazilian kids compute as street vendors. and even more interestingly, while this algorithm appear more complicated to most of us, it is more comprehensible to the kid than what is taught in school. well, a group of researchers conducted a experiment. they tested these kids on the streets with computations while posing as buyers. they then tested them again in school with similar computations with paper and pencil at school. as you would have guessed, the kids fared significantly better at mental calculations on the streets.

the following is an example. one girl when asked how much would 12 lemons cost, if each lemon cost 5 cents each, replied 60 correctly. But when asked to compute 12 times 5, and with the aid of paper and pencil, she actually came up with the answer 152.

as devlin tried to explain, and as u can guess, when endowed with a meaning, math is easier to understand and master. in fact, human beings have an innate math instinct, which was developed through evolution. and in the book, he brought up many examples of this math instinct which are present in dogs, lobsters and even plants. unfortunately, some of these examples are rather contrived and his exposition got a bit incoherent in the middle. but some are really intriguing and illustrate well the math instinct. for example, a dog exhibited the ability to do calculus, by finding the fastest way to retrieve a ball in the river.

another example was rather coincidental. in a recent navigation examination, we were supposed to learn to ascertain our position on earth after we sailed a number of courses at certain speeds. it’s a bit complicated cos we need to account for the earth’s curvature and such. however, a Tunisian ant is able to perform the above task without any difficulty. basically, when the ant goes out in search for food in the desert, it twists and turns and crawls in various directions. at the end of the day, when it is done, it calculates and heads home in a straight direction without retracing its steps (the book also explains that it was not due to other factors like scents..).

frankly, the book seems rather disconnected and it’s like a collection of articles which have some link to the theme. but the concluding chapter states an interesting proposition, that math is really formalized or abstract common sense. an idea which i’m q fond of (but the author agrees only to certain extent. n the reason is too deep for the book…). mathematicians reason in a manner like any other ppl, but in an environment without context nor tangibles. and it is precisely this lack of context that makes math so distant to ppl and yet so powerful. powerful cos it enables one to transfer ideas from one environment to another in such ingenious manner.

talk too much le. my course ending soon… ie I’ll be back onboard ship and sailing… no more undisturbed weekends and evenings le… so sad…

anyway, the book is still q interesting, cos of the first and last few chapters. haha.