# ‘I’m no good at maths’: how did you reach that conclusion?

## That’s Maths: We hardly notice it, but we’re in mathematical mode all the time, whether driving, laying on a bet or buying a house

Bragging about mathematical ineptitude is not cool. There is nothing admirable about ignorance and incompetence. Moreover, everyone thinks mathematically all the time, even if they are not aware of it. Can we all do maths? Yes we can. We use simple arithmetic every day when we buy a newspaper, a cinema ticket or a pint of beer. But we also do more high-level mathematical reasoning all the time, unaware of the sophistication of our thinking.

The central concerns of mathematics are not numbers but patterns, structures, symmetries and connections. Take, for example, the sudoku puzzles that appear daily in The Irish Times. The objective is to complete a 9×9 grid, starting from a few given numbers or clues, while ensuring that each row, each column and each 3×3 block contains all the digits from 1 to 9 once and only once. But the numerical values of the digits are irrelevant; what is important is that there are nine distinct symbols. They could be nine letters or nine shapes. It's the pattern that matters.

Another Irish daily paper publishes these puzzles with the subscript, "There's no maths involved, simply use reasoning and logic". It seems that even the idea that something might be tainted by mathematics is enough to scare off potential solvers. Could you imagine the promotion of an exhibition in the National Gallery with the slogan, "No art involved, just painting and sculpture"? If you can do sudoku, you can do maths.

Whether you are discussing climate averages, studying graphs of house prices, worrying about inflation rates or working out the odds on the horses, you are thinking in mathematical mode. On a daily basis, you seek the best deal, the shortest route, the highest interest rate or the fastest way to get the job done with least effort. The principle of least action encapsulates the fundamental laws of nature in a simple rule. You are using similar reasoning in everyday life. Maximising, minimising, optimising: that's maths.