Thanks for the reference to The Hitchhiker's Guide. Probably, humor ties happiness and depth together, or misery and happiness, or something or other. Sheet! I don't know. Maybe you can explain it better than I can.
I can't really remember ever being happy. Oh, I've had my fleeting moments of happiness, but in my search for meaning--probably as an escape from misery-- fell down a well metaphorically. That's where I found true depth, but nothing in the intellectual sense. I don't think happiness or depth comes through the intellect. The intellect bings this: "Answer to the Ultimate Question of Life, the Universe, and Everything (42)". For those of you who aren't familiar with this statement it's the ultimate statement from the "hitchhiker's guide to the Galaxy".
I've found my relationship to the universe, which is my definition of religion, and I don't think the universe is an especially happy place, but the perception of it--with its good and bad--can be sublime.
Now, would I trade all this depth for happiness? In a second.