The kid and I talk now and then about laws and social norms and law enforcement and things like that. I didn't expect it to show up in such an unexpected setting.
The kid and I are studying (algebraic) variables. She was making some headway with them, then got stuck on programs, so we went back to paper and algebraic formulas. Progress restored. I give her `x + 2 * y`. She thinks she's got it. Then she stops.
- Daddy, I have a question.
- Sure, what is it?
- I'm not sure what the answer is.
- Why not?
- I'm confused about what this is.
- Can you tell me why you're confused?
- Well, I can't tell if it's x plus 2-times-y or x-plus-2 times y.
So we work out what the answers would be, and that they'd be different, so it does matter. I tell her there are three options. I show her (infix) parentheses. I tell her there are different notations we could use and draw her a parse tree. Or, I say, we could just decide that we do the multiplication before the addition.
- Is that a rule?
- Yes, that's a rule.
- I mean, is that a real rule?
- What do you mean?
- I mean, is that just a rule you're making up or do other people also follow that rule?
- No no, other people use it too.
- But we don't have to use it, right?
- No, really, we should. I mean, other people would expect you to use it.
Pause. Eyes get bigger. A slight look of concern crosses her face.
- The police? #parenting