I'd had the pleasure of answering kids in the 'why' stage before having kids of my own. And resolved to face my own kids with answers whenever I could.

I'm not sure it has been successful, they never really exhausted my ability to answer but I fear it may have sucked out some of the magic - not having answers might be 'better' to some extent if your aim is to foster curiosity and personal goal fulfillment.

My kids are awesome and definitely have some intrigue; but perhaps endeavour to not provide answers!

My eldest in some ways skipped the "why" stage. "How" was a much more important question to him. Although, he did ask his mother once why the sun was on fire, but she passed him off to me on. Because his questions were often complex, and outside of my expertise, I would often say, "I don't know", usually followed by, "we can look it up, though".

One of the key lessons of physical science is that "why" is the same as "how". "Why" is a psychological layer, how we thinking about "how". There is no "why" in physics.

That's quite true in physical science. However, physical science is a fairly new endeavor. The "why" may not be entirely psychological, but mathematical, at the end of the day.

Have you seen the Louis CK bit about that? The relevant bit starts about 7 minutes in. https://www.youtube.com/watch?v=IR8Um_vZ3oM

I thought you were linking this: https://www.youtube.com/watch?v=Dp9atyHwQF8

Both bits are quite nice.

For my own son at a certain point I stumbled upon the strategy of not providing him with real answers (most probably because I myself didn't know the answers) but instead sharing in his curiosity with him and saying things like "wow that's interesting, I've never thought about that. Maybe this happens because of X, or Y. Do you think it could be because of Z?" Like Joan quoted above - at some point in their age providing answers takes the fun out of things for them. Or rather closes their curiosity and inclination to further think about the question. I feel now my job is to encourage them to not limit themselves and develop more independence in thinking about things themselves.

The crucial difference is whether you try to answer all questions, or whether you discuss and reason about possible answers together.

This was not easy (reason with a 2-3yo) but it's starting to become easier as time passes by.

Ditto! I also try to never tell the kids "don't ask that question." Though very often I do need to answer with "I don't know, but let's find out if anyone does," then research it later. And occasionally, as recently happened when the question was about the Vietnam war: "that is a very long and complicated story, give me some time to figure out a way to explain a little bit of it."

My kid has just turned two. He hasn't started with "Why" yet, but I am excited for it.

I love the idea of coming up with endless possibilities, labeling realistic ones and why (important) but enjoying the flights of fancy for what they are too!

"Why yes kiddo, I would love to ride a Rainbow-unicornDragon-with-tentacles to work!"....

Thanks for doing this. The world will thank you now and later. And I'd bet she will turn out to be an amazing person.

I bet she already is.

It is also fun to reply, "Why do you think?" I got this idea from someone who was (momentarily) tired of answering their kids, but I think it's good because a) it helps them reason things from principles b) you sometimes get really neat or at least amusing answers.

This is a common trait, I was the same, I call kids like this “why birds” after a BBC character.