What do you see as defensive fighting?

Dodging/slipping?
Counter-punching/counter-kicking?
Parrying/blocking?
Leaving openings to capitalize on your opponent's attack?

In boxing and other competition fighting everyone would agree defensive strategies are useful, or even essential. What about on the street? Surely it's more important to show downright aggression and give no quarter? Of course, this depends on the kind of person you are: naturally non-aggressive people have to work on their agression and proactiveness, and will have a natural disadvantage compared to a naturally animalistic all-out aggressive kind of instinctive fighter.

I would think...

Discussion, argument, flame welcome!

Happy New Year!