Shadowdragon posted the following on a different thread:
Internal vs. External
Internal External
Blending with an attack Stopping an attack
Yielding Struggling
Power comes from within Power comes from outside
Relaxed Tense
Fluid Defined
Slow forms Fast kata
Finesse Power
Indirect Direct
Circular Linear
Accepting what is Fighting against it
Acknowledging the
limitations of the self Denying any vulnerabilities
Winning without
fighting is best Destroying your opponent
Before anybody gets their panties in a wad, note the complete title of the thread–it’s an intellectual exercise, not a threatening challenge to internal artists or boxers 
Now, I realize the above is not necessarily a comprehensive breakdown, but it seems to me that based on those qualities, boxing shares far more in common with “internal,” vs. “external.”
Let’s examine the first issue–blending with an attack. In boxing, active hard blocking does not play a prominent role. Passive blocking does in the sense that you’ll take it on your forearms instead of your face if you have to, but ideally, you’d rather redirect with a parry or slip it or a combination of the two. Some people DO block–but rarely will you see it considered “good” to throw a hard block out there.
Yeilding–Boxers roll with the punches. If they get hit they might use that momentum as the first part of a big slip to avoid the rest of an incoming flurry. They might also use that momentum to get their whole body moving, taking the sting out of the shot, and setting up for a counter of some kind.
Power comes from within- Nobody has yet provided me with a reasonable explanation of this. Does this mean that power is channeled through your center? If so, then Boxing accomplishes this. There is no punch in boxing that does not derive the great bulk of its power through proper structure and torso movement. Arm punching is discouraged and also, next to useless
Relaxed–a tight boxer is a bad boxer. Next.
Fluid-- Boxers are always moving, but rarely straight forward or back. Punches must flow from one into the next. Movement must flow from the punches and vice versa. If you aren’t fluid and relaxed you get hit and can’t hit back. Footwork is dynamic, well balanced, and almost constant. Bouncy is bad.
Slow Forms–While boxing does not have forms as such, shadow boxing at slow speeds is often encouraged, as is slow repetition on a bag to ingrain certain body movements–speed can be added, but NEVER at the cost of fluidity.
Finesse–Accuracy and counterpunching, coupled with movement, make a true “boxer.” Mike Tyson, in his early years was a fantastic “boxer.” He moved in and out easily, slipped most shots, and had uncanny accuracy with hands that happenned to be made out of sledgehammers. Ali was another very good “boxer,” when he wanted to be. Watch Roy Jones Jr. sometime. Sure, he’s got power, but he finesses his way into setting up that power.
Indirect- Boxers are ALWAYS taking angles–boxers are ALWAYS trying to draw the other guy out of stance and unbalance the opponent to take advantage with an unexpected attack from an angle that the opponent has a hard time countering in time, rather than battering through defenses to reach the body.
Circular-- Boxers circle to facilitate indirect attacks. Even if the boxer is moving in or out in a relatively straight line, they will be slipping in a circular manner as they step, to set up angles and avoid getting hit.
Acknowledging the limitations of the self–I’ve never met a boxer that really LOVED to just weather a storm of punches. Slipping, weaving, elusive footwork, parrying, etc. All are ways in which it is acknowledged that you, as a boxer, are vulnerable and human and have limits. “Take the pain,” isn’t very popular. It’s nice if you can, but boxers would rather work on how NOT to take the pain, while understanding that they WILL sometimes get hit. Practice is to improve your skill, not to make you into some uninjurable superhuman.
Winning without fighting–well, you got me here-- It’s a duel, so you HAVE to fight. But that’s the nature of sportive combat–I don’t see people who do San Shou with a Tai Chi background just running away the whole time. So, if we look at it from “self-defense,” perspective, then boxing coaches almost always tell you to run, rather than use your skills.
Thoughts?
