Hebei vs Shanxi

To the people who have or are currently practicing internal martial arts, specifially Xingyiquan, much of this information will be redundant. I have always classified martial arts according to the following hiearchy: system - style - techniques. A system therefore could contain numerous styles or be a conglomeration of many different apects of styles. A style is a distinct martial art within a system and the individual techniques are categorized within the style (striking, kicking, iron palm, shuai jiao). I consider Xingyiquan a super system comprised of three main subsystems - Shanxi, Hebei, and Honan. Honan or Hunan as it is sometimes called is arguably the oldest and least derived due to the fact that it wasn't even shared with the public until recent history. Hebei style is the most derived while its sister Shanxi  is a little lower on the evolutionary ladder. The reason I classify each as systems of a larger supersystem is that there are numerous individual styles that are very distinct from each other. The reason for this is that Xingyiquan is a highly personalized style and nearly every indivudual who masters it will innevitably make changes according to their understanding, individual execution, and physical makeup.
I practice Shanxi style xingyiquan. Shanxi is best characterized as  more "external" or simply stated uses more muscular effort than Hebei whose movements can be likened to Taiji practice. The movements of Shanxi are also a bit more flambouyant than Hebei giving it an old school Shaolin flare. Both Shanxi and Hebei have 5 fists, twelve animals, a 5 element linking form, and an An Shen Pao - two man practice routine.
 Hebei is probably the best known and most practiced of the three due to the fact that its techniques were greatly publicized by Sun Lu Tang who left a thorough literary review of the style. The Shanxi practitioner will exhibit flowing movements with burts of incredible speed near the moment of impact. His counterpart, the Hebei practitioner will perform the movements in a slow and steady manner much as would a Taiji performer. The Hebei stylist will concentrate on a flowing execution and his movements will largely be confined or less remarkable than a Shanxi practitioner's.

What is the difference between the two? Not much really. One can readily see the combat application of Shanxi but might be perplexed at how Hebei could be beneficial in a fight due to its rythmic and soft nature. When its time to fight there will be little difference between the two stylists other than choice of techniques and execution. The blows will be sharp, quick and devastating.

In comparing the similarities and differences between the styles one can see a remarkable example of how the old addage "there's more than one way to skin a cat" is true. The difference between the two lies in the training and practice. Both Shanxi and Hebei practitioners can hit hard and execute movements at breathtaking speed with accuracy. The Shanxi practitioner merely practices in the manner most similar to the real time execution of the moves. That is not to say that Shanxi is superior to Hebei. It's not. It's merely another method of arriving at the same place as would a Hebei student. The Hebei student develops soft power by thoroughly relaxing the tendons and muscles as one would when practicing Taiji. The continuous soft practice strengthens the body and develops awesome power. Shanxi practitioners develop the same power by the isometric tension and release of their muscles. Both practitioners must test their strikes on heavy bags and in the manner that would be expected in a real fight. It would do no good for the Hebei practitioner to strike an adversary with a butterfly hit.