it does not tell us the reason why it burns.

But you will ask, "If that is not the reason why fire burns, what is?" My
dear child, I do not know. That is Lady Why's business, who is mistress
of Mrs. How, and of you and of me; and, as I think, of all things that
you ever saw, or can see, or even dream. And what her reason for making
fire burn may be I cannot tell. But I believe on excellent grounds that
her reason is a very good one. If I dare to guess, I should say that one
reason, at least, why fire burns, is that you may take care not to play
with it, and so not only scorch your finger, but set your whole bed on
fire, and perhaps the house into the bargain, as you might be tempted to
do if putting your finger in the fire were as pleasant as putting sugar
in your mouth.

My dear child, if I could once get clearly into your head this difference
between Why and How, so that you should remember them steadily in after
life, I should have done you more good than if I had given you a thousand
pounds.

But now that we know that How and Why are two very different matters, and
must not be confounded with each other, let us look for Madam How, and
see her at work making this little glen; for, as I told you, it is not
half made yet. One thing we shall see at once, and see it more and more
clearly the older we grow; I mean her wonderful patience and diligence.
Madam How is never idle for an instant. Nothing is too great or too
small for her; and she keeps her work before her eye in the same moment,
and makes every separate bit of it help every other bit. She will keep
the sun and stars in order, while she looks after poor old Mrs. Daddy-
long-legs there and her eggs. She will spend thousands of years in
building up a mountain, and thousands of years in grinding it down again;