I thought that Cac really was a musician therefore I assumed that the reason he doesn't want to talk about his job is that it is just a job and not his purpose.
No...I already said that the reason is that it is difficult to discuss something so obscure and technical with someone who has no basis for understanding of the subject. I wonder about the "purpose" thing, though. I don't know if my "job" is my "purpose", or not. I've said that if I were to win the lottery, I would't quit my job. It gives me a sense of "purpose", certainly. I like what I do; it suits me, and I get a great deal of satisfaction knowing that I provide an essential contribution to a worthwhile enterprise.
Maybe if he played flute in some sort of ensemble on a regular basis that would be something he would feel like talking about.
funny you should mention that. I recently started doing just that. I can, and have talked about that...not a problem, because this particular endeavor is one in which we share a common background. I couldn't talk to you folks about that subject, except in a fairly superficial manner, for the same reason I can't talk to W about "what I did at work today": its kinda obscure, and I'd have to compose posts of fearless-length to explain the tiniest little point. But I can walk in the door after a rehearsal (where I was playing piccolo for the first time in many, many years,) look at W, shake my head and say "F#%^*-ing ledger lines!!", and I've just transmitted volumes with a mere sentence fragment, and a cuss-word.

Also, unless I'm remembering wrong, MrsCac is a musician too. So why don't they do musical things together as a family? Like they could train the kids and then they could be like the Von Trapps or The Partridge Family or something like that.

While that does make for entertaining television, I'll admit, Its not quite as easy as they make it look on tv. for one thing...we've only got 1 kid.
But yes, W and I met in music college; we both have music degrees, "music" brought us together...(well, that, and the fact that she let me eat fries off her try in the caff). And we have done some stuff together, but not much. While we share a very similar history and core education, our musical pursuits are actually very different. hard to explain. Imagine, if you will, a mechanical engineer, and an electrical engineer. You could follow either of those disciplines at the university we attended, both under the same "college of engineering". If you look at their respective courses of study, the first 2 or maybe even 3 years are nearly identical. But the application of that same math/science is actually very different. Kwim? Works the same way in the music world, too.