> You think a good way to tell whether I'd be good at
> writing code is my opinion on philosophy outside my
> domain of expertise?
In the case of the physics student it was just their passion, they had gone way beyond the course work because they were interested in interesting questions.
Except that is EXACTLY the correct response -- "I don't know, but I understand that physicists have a good idea of what space-time is, and I'll review the literature and see what the scientific consensus is and we can work from there."
The exact WRONG answer, in real life if not the interview, is "Hrm, I'm not sure but how about I make something up on the spot!"
When I said (paraphrased) "I don't know, ask someone else" I meant literally that. People who are asked a question about something they don't know anything about can either, do as you suggest propose a way to research the question (win), or do as I've observed refuse to go any further (lose). People who make things up on the spot generally are weeded out before we got to that point.
To be clear, I don't think the correct answer of "I don't know, but I'll do a review of the literature and see what the scientific consensus is" is what the interviewer was hoping for, which is my contention.
It's not going to be accurate, but that is not the point. The point is whether you return a blank stare or start trying to reason and analyse the problem.
Sure, you might end up with any number of "I have no idea what the right value for this is - if it wasn't an interview, I'd look it up, but for the sake of argument let's say the value is X". That's fine. Your ability to make that leap and continue is more important than the right result (so is your ability to recognise and admit that you don't know and are substituting guesses)
Do you think speculation on things that are an inferential step[1](or a couple of steps) away from things you currently know could be a gauge of a person's innate intelligence?
Intelligence is required to make inferences. Assuming a common starting ground, a person who could make the most logical inferences from it to explain a result would suggest that he's smarter. I do not claim to say a person who makes 10 good points is less smart than someone who makes 11 good points. But he surely you can agree that a person who is able to make 0 inferences is likelier to be less intelligent than someone who makes a hundred.
[1] Where my idea of inferential step is taken from - http://lesswrong.com/lw/kg/expecting_short_inferential_dista...
No, I do not. It introduces a large capacity for things to go wrong, and it is very difficult for the interviewer to separate themselves from process. Speculative development is a road marked by dozens or hundreds of failed efforts before you hit on success. Either the interviewee happens to hit upon one of the few "correct" answers in the time available -- password guessing -- or some tolerance of wrong answers is to be accepted. But it is quite difficult to differentiate bad speculation from fruitless speculation, in a way that usefully differentiates candidates based on capability.
My guess is Google has plenty of bad programmers, or worse Imposters.
So don't think that this is the typical Google interview. :-)
In high school we were creating a vacuum in a bell jar to do the 'drop a feather and drop a weight' experiment and my physics teacher asked it. "So if we didn't have our apparatus in there, and we sucked it dry, what would be in there?"
It makes a great interview question because it helps identify people who have a hard time holding an unknown concept in their head and working with it.
I asked that of one of the folks I interviewed for Google when I was there and we spiraled off into a discussion of branes and multi-dimensional manifolds and quantum wave equations[1].
[1] Fun interview and they got the job :-)