Chapter 4

"So, did you ever study geometry?" Richard asked me.

"Sure," I answered. "In high school."

"Tell me, then: what do you do in geometry class?"

I blinked at this unexpected question. I had prompted it, somehow, by complaining that I didn't understand how to go from the stated problem to a program for solving it; but for the life of me I couldn't see the connection.

"Well... ," I began hesitantly, "you draw figures..."

"Geometry," Richard said, "not art."

I gave him a glare, but really, he was too cute for me to be mad at him. "All right," I started again. "You do proofs."

"Exactly!" Richard smiled at me as if I had just won a gold star. I found myself smiling fatuously back. Brother. I disgusted even myself.

"Writing a program," he went on, "is just like constructing a proof. You are given certain things. You have precise rules for how to combine them to get new things. You have to write down a rigorous, step-by-step procedure to go from the given to the conclusion. Except," he raised a finger for emphasis, "writing a program is easier than proving a theorem, because with a theorem you don't necessarily know whether the conclusion is correct, or how to show it; while with a program, you are usually carrying out some fairly well-defined procedure."

"Geometry was my favorite math class," I mentioned. This was actually true. I remembered the first couple of weeks of class, being bewildered, uncertain about what it was we were supposed to do. Then suddenly, it had all clicked, and I had loved it after that.

"If that's so," Richard said, "then by the time we're done with you you're going to love computer science."

I think I may love it already, I thought, but probably not for the right reasons. Oh, well. Give me time.

Step by step.

Match point.

Arlene was bouncing the ball with her left hand, watching me across the net. It was pretty early yet, and the air was cool, but we had both worked up quite a sweat. The two of us rarely played tennis together -- Arlene liked to play "for fun," and I had difficulty restraining my killer instincts, so it seemed better to play with other partners rather than risk our friendship over a game. Today, though, Arlene had decided that she needed exercise, and I had agreed to a couple of friendly sets. I had promised myself to take it easy and just have a good time.

My good intentions proved unnecessary, since Arlene had proceeded to beat my tail all around the court. For some reason my concentration was shot all to hell. Arlene had broken my serve a humiliating four times, taking the first set easily, and was about to do the same with the second. In the meanwhile I had given up no fewer than nine aces, double-faulted seven times, and failed to break her serve even once.

Her first serve was long. Arlene pulled a second ball out of her pocket, bounced it a couple of times, then threw it up and smacked it towards me. I tried to get my breathing under control and focus on the ball. It was a nice, easy hit, careful to be in bounds; I returned it with no trouble. We rallied back and forth a few times. To hell with friendly, I thought, and charged the net. Arlene acquired a slightly panicked look and hit the ball towards me. I returned it hard, but not quite hard enough; Arlene managed to catch up with it and send it wobbling back. I dove left; the ball went right. Game, set, and match.

"You know," Arlene told me while we were sitting on the bench afterwards, "that was really good for my ego." She scrubbed her face off with a towel and added, "Of course, it would have been even better if you'd been playing in the same court with me. What was up with you today?"

"Nothing," I said. "You were playing really well."

"Sure, sure," Arlene said. "Come on, when's the last time I beat you in straight sets?" She thought about it for a moment. "For that matter, have I ever beaten you in straight sets?"

"Ummmm..." I shrugged. "I dunno. I was feeling kind of distracted."

"Distracted," Arlene said skeptically. "Right."

I shrugged again. "Richard says that half of all problem-solving is the ability to focus on a problem without getting distracted," I offered.

"Ha!" said Arlene cryptically. She took a swig of Gatorade.

"What does 'Ha!' mean?" I asked her with some irritation.

"Well, 'Ha!' can mean lots of things," Arlene answered. "In this case, it means: that's the third time this morning you've started a sentence with the words 'Richard says.' "

I felt my face heating. "So?"

" 'So?' " Arlene said mockingly. "So, when did Brad get replaced?"

I stared at her like an idiot, and she sighed. "Oh, please. It's obvious you've got a thing for this Richard guy. You can't fool me. I know all. So, go on, spill it. What's he like? Have you kissed him yet? Tell Arlene everything; you'll feel better for it."