Morioka scoffed loudly. He crossed his legs off to the side of his chair. “What good’s differential and integral calculus gonna do me? It’s a waste of time.”
Ishigami had turned to the blackboard to begin an explanation of some of the trickier problems on the year-end exam, but Morioka’s comment made him stop and turn around. This wasn’t the kind of thing he could let slide. “I hear you like motorbikes, Morioka. Ever watched a race?”
Morioka nodded, clearly taken aback by the sudden question.
“Well, do racers drive their bikes at a set speed? No, they’re constantly adjusting their speed based on the terrain, the way the wind’s blowing, their race strategy, and so on. They need to know in an instant where to hold back and where to accelerate in order to win. Do you follow?”
“Yeah, sure, I follow. But what’s that got to do with math?”
“Well, exactly how much they accelerate at a given time is the derivative of their speed at that exact moment.
Furthermore, the distance they travel is the integral of their changing speed. In a race, the bikes all have to run roughly the same distance, so in determining who wins and who loses, the speed differential becomes very important. So you see, differential and integral calculus is very important.”
“Yeah,” Morioka said after a confused pause, “but a racer doesn’t have to think about all that. What do they care about differentials and integrals? They win by experience and instinct.”
“I’m sure they do. But that isn’t true for the support team for those racers. They run detailed simulations over and over to find the best places to accelerate—that’s how they work out a strategy. And in order to do that, they use differential and integral calculus. Even if they don’t know it, the computer software they’re using does.”
“So why not leave the mathematics to whoever’s making the software?”
“We could do that, but what if it was you who had to make the software, Morioka?”
Morioka leaned further back in his chair. “Me? Write software? I don’t think so.”
“Even if you don’t become a software engineer, someone else in this class might. That’s why we study mathematics. That’s why we have this class. You should know that what I’m teaching here is only the tip of the iceberg—a doorway into the world of mathematics. If you don’t even know where the door is, how can you ever expect to be able to walk through it? Of course, you don’t have to walk through it unless you want to. All I’m testing here is whether or not you know where the doorway is. I’m giving you choices.”
As he talked, Ishigami scanned the room. Every year there was someone who asked why they had to study math. Every year, he gave the same explanation. This time, since it was a student who liked motorbikes, he’d used the example of motorbike racing. Last year, it was an aspiring musician, so he talked about the math used in designing musical technology. But no matter the specifics of the discussion, which changed from year to year, it was all old hat for Ishigami.
