There's a subject — maths, maybe, or spelling, or something at school — that you've decided you're just "not a [whatever] person." You say it almost proudly now: "I'm rubbish at maths." It's become part of how you describe yourself, like your eye colour. Here's the thing, though. Saying it has a side effect. The moment something gets hard, you've got a ready-made reason to stop trying: well, I'm not good at this anyway. So you don't really try, which means you don't get better, which proves you were right all along. It's a tidy little loop. Today the teacher set something tricky, and you felt the familiar shrug coming on. Not my thing. But a small part of you wonders whether the label is the cause, not just the description.