Being All Inclusive
In the middle of a conversation with his grandmother yesterday, my six-year-old son Alex excused himself to look at an item in her house. He returned and, addressing no one in particular, announced, “There are 24 buttons shown in that picture. It’s a 4 × 6 grid.”
“I’m so sorry,” I said to my mother-in-law for raising a son who would walk away from a conversation with her. “I’m sorry to you, too,” I then said to Alex, for conditioning him to look at everything with a mathematical eye and, ostensibly, for making it impossible for him to shut if off. (It should be noted that Alex’s dad has the same affliction.)
As another example, I told the boys that if they could figure out how much change I had in my pocket, they could split it for their piggy banks. “I have two types of coins, with twice as many of one type as the other. And the value of my coins is between 20¢ and 25¢.” Alex then asked:
You mean between 20¢ and 25¢ inclusive?
And why wouldn’t he? Isn’t that the question than every normal, well adjusted six-year-old would ask in the same situation?
Taking a walk with Eli this morning, we encountered this sign:
I asked Eli, “Do you think I’d get in trouble if I were in this park at 8:30 p.m. on October 1?” He said I would, that the park is open till 9:00 p.m. through September 30, and then it switches to the early hours on October 1. I suppose I agree, but I’d still argue that the sign could be less ambiguous.
These experiences remind me of a joke.
The law of inclusion-exclusion either rules or does not rule.