“That’s largely to reflect the different needs of society,” he says. “No one ever in their real life anymore needs to — and in most cases never does — do the calculations themselves.”
Computers do arithmetic for us, Devlin says, but making computers do the things we want them to do requires algebraic thinking. For instance, take a computer spreadsheet. The computer does all the calculations for you automatically. But you have to write the macros that tell it what calculations to do — and that is algebraic thinking.
“You cannot become good at algebra without a mastery of arithmetic,” Devlin says, “but arithmetic itself is no longer the ultimate goal.” Thus the emphasis in teaching mathematics today is on getting people to be sophisticated, algebraic thinkers.
That doesn’t mean that kids can skip learning their multiplications tables. “But the way it’s taught now is you get to the multiplication tables by understanding the number system and understanding what numbers mean,” Devlin says.