Many introverts are good empaths. They respect others just as much as they would wanna be respected. They're shy around people because their sensitive to others' dignity as well as their own. They know their limits so they can tell when a person needs some space.

An introvert might also be aloof due to high sensitivity--indeed, their introversion may result in part from the mental and emotional overstimulation that other people cause, especially in group settings.

So while it may appear that the introvert is stand-off-ish, they are actually protecting themselves from sensory overload, and in a one-on-one situation might be able to go deeper with the other person than an extrovert.

I've always describe introvert as: everything begins and ends in the self. In other words, introverts are kind of the pack rats of reality: going out into the world and gathering representations of reality which they carry back to their own little hole and work with. While, for the extrovert, everything begins and ends in the world of objects.

But saying introversion and empathy are synonymous, or at least complimentary with each other. After a longer look at the two meanings, I want to disagree. Empaths may pick up other's feelings whether they want to or not. Being an introvert can be a coping mechanism in that case.

Regardless of the oversimplified dichotomizing, introverts draw their energy internally, extroverts externally. This seems have to do with the dominance of their acetylcholinergic and dopaminergic systems, respectively. Either could be empaths, but draw from different bases. In this perspective, the introvert could actually be more empathic, given they get past the social barrier. But overall, neither is black or white; we are talking about continuum of functioning.