[throwaway918274]

My first job interview out of college, the interviewer's last question was "what is the Eigenclass". I had no idea, so I just said "I don't know, what is it?" - and then we just chatted about what it was. I'm convinced I got that job because I was 1) honest that I didn't know, 2) was curious enough to ask about what it was and learn about it from a potential colleague. That one question taught me A LOT about what it means to be a professional developer as a fresh grad.

Many years and companies later I now use that same question when interviewing Ruby developers for $DAY_JOB. It's an excellent way of knowing if they're a ruby developer or just a developer that knows ruby.

To this day, no other interviewer has ever asked me what the Eigenclass was.

[1123581321]

If someone tells you they don't know, do you hire them? :)

[vidarh]

Maybe. If they can talk about the topic once I've explained it in a way that makes me convinced they're a fast learner. I'd take a fast learner over someone who knows more but I'm not convinced can go much further almost any day.