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Comment by stickperson | Hacker News Reader

Cool idea, and the site looks nice. That being said, I was lost by the end of the first section.

I think calling a DE "a fact about the derivative of a function" and then speaking about "solving it" in the same sentence is a big source for confusion, since we don't usually "solve facts".

EDIT: reading the whole thing, there's quite a bit of sloppiness and stuff that's flat-out wrong, like " the faster the cart goes, the faster it stops", or the statement at the end claiming that nonlinear DEs don't have solutions. In short: this needs a major cleanup.

All equations are facts (or, more accurately, propositions) and solving an equation is deriving another proposition that is implied by that proposition (or perhaps that proposition and another proposition, such as when solve an equation in one or more unknown for a set value of one unknown.)

OTOH, you are correct to the extent that we don't usually use both the "fact/proposition" language and the "solve" language at the same time when discussing equations.

Exactly. I quite like the idea of calling a DE a fact about the derivative of a function, it's just the juxtaposition that is confusing.

If it from the latter sentence means the derivative, the sentence makes sense, because with y'=f(x,y(x)) we wanna solve the equation for y.

I think it would be helpful to define a derivative first.

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