One page, three ways to work at a topic — and not one of them hands you a finished answer to copy down.
Why does ice float on water?
YouWhy does ice float on water?
BonsaiBecause water is odd: it is one of the few things that expands as it freezes. Below 4 °C the molecules lock into an open hexagonal lattice held apart by hydrogen bonds, so the same mass takes up about 9% more room — lower density, so it floats.
Before we go on: what would happen to a lake over winter if ice sank instead?
BonsaiPick a concept and start teaching it to me — I'll ask questions as we go.
YouIce floats because it is lighter than water.
BonsaiLighter how? An ice cube is lighter than a swimming pool, and a glacier is heavier than a bucket of water — both still float. What is the property you actually mean, and what happens to it when water freezes?
YouIce floating is just a quirk of chemistry. It does not really matter.
BonsaiIt is a quirk with a body count. If ice sank, lakes would freeze from the bed upward and the ice would sit below the reach of summer sun — so they would stay frozen, and nothing overwintering in them would survive.
You may still be right that it is incidental rather than designed. Make that case and I will tell you where I think it gives way.
Start where most people start: there is something you do not understand and you would like to. Ask it in whatever words you have — Ask anything is the whole of the instruction — and Bonsai explains the subject rather than answering the narrow question you happened to land on and stopping there.
Ask the follow-ups. Ask the embarrassing ones, the ones you would not ask in a seminar with thirty other people in it. It is a tutor, not an audience.
Now the roles switch. You explain the concept to Bonsai, and it asks the sharp questions — the ones that find the seam in an explanation that sounded perfectly solid in your head thirty seconds ago.
Teaching something is the fastest way to find out you only half know it. Explain exists to make that happen on purpose, in private, before an exam does it for you.
It does not simply agree with you. When your account of a thing has a hole in it, you get asked about the hole.
A Socratic seminar with unlimited patience. Make your case; Bonsai probes the weak joins, offers counterpoints, and — this is the part that matters — concedes when you are genuinely right.
A model that caves at the first push is not teaching you anything, and neither is one that argues forever out of stubbornness. Discuss is for essay lines, interpretations, and the sort of question that has more than one defensible answer.
Every teacher has the same objection to putting a general-purpose chatbot in front of a student: it will do the homework. Ask it a question from the problem set and it produces the finished answer, the student writes it down, and nothing whatsoever has been learned.
Bonsai is built the other way round. The tutor works in hints and questions — enough to get you unstuck and moving, never a completed piece of work to transcribe. That is a deliberate constraint on the product, not a limitation of the model.
It is also why Bonsai is worth handing to a class. Our mission goes into what we are trying to do with it.