There are no styles in karate-do; but even the rawest beginner will tell you that the styles taught in other dojos are inferior to the style taught in his. Shotokan is too long-range, Wado-Ryu is weak, Kyokushin is just brawling, Goju-Ryu is brutal, and so on. Evidently the first statement must be wrong: karate-do is broken up into a myriad of competing styles, yet karate-do has no style. How are these conflicting statements to be reconciled?
The practice of karate-do is the beginning of a journey, and almost all journeys can follow different paths but end at the same place, some by the direct route, some by the pretty route, some visiting interesting diversions on the way. Likewise the journey towards karate-do can be undertaken by different routes, and the different styles take the student in different directions before ending up at the same place.
To understand the evolution of styles in karate one needs to understand the evolution of the practitioner of karate, the karateka. At first there is study, repetitive study and practice, repetition, repetition, repetition to the point of tedium and beyond, burning into the brain and muscles the basic techniques of fighting, identifying the natural weapons we possess, and learning how to develop and use them. This is the first stage; most of us never progress beyond this. The second stage is the transmission: having become accomplished in the fundamental skills, the karateka refines his understanding by continuing practice and also, and this is important, by teaching. Anybody who has ever taught anything at all knows that preparing to teach exposes weaknesses in ones own knowledge, and that the best way to learn something properly is to prepare to teach it. A few karateka are sufficiently advanced to teach. The third stage, the culmination of the technical development is divergence. Having explored fully and having mastered a style, the exceptional master might diverge, change the style in accordance with his unique insights, and teach this different style to his students.
There are subtly divergent versions of Shotokan karate which are all based in the teachings of the original founder of the style, Gichin Funakoshi. Though they are all referred to as Shotokan, and while they all share the fundamental principles set out by the founder, they alter his original teachings in the light of modern knowledge about physiology and kinesiology, or by the addition of supplementary material. For example, Funakoshi believed that competitive free-fighting was far too dangerous to be permitted: some of his followers disagreed, and developed the sport of tournament karate in parallel with the martial art he founded.
Shotokan karate is the most popular style in the world: it is the beaten track of the journey to karate-do. The most important benefit of following the well-trodden path is the benefit one receives from the many who have been that way before. This is reflected in the publication of instructional manuals, videos, and by the large number of inspirational teachers and leaders of the style. One of the most respected karateka in the world is Hirokazu Kanazawa, 10th Dan, Kancho (president) of the Shotokan Karate-Do International Federation (SKIF). He is a prolific author and a charismatic instructor who, though born in 1931, still undergoes an exhausting schedule of international travel to visit the dojos in the SKIF.
The less-travelled roads have their charm. Some people prefer to join less popular styles because they don't care for the crowds, or take the view that karate is bound to be coarsened through mass-participation, stripped of subtlety and mystery; but the problem with the less-travelled roads is the lack of maps, and without a map it is easy to get lost and to miss the destination, and worse, not realise it has been missed; and that is why it seems prudent to many of us to follow the road opened to karate-do by Kancho Kanazawa. This is the way taught by the Shi-Gaku-Kan dojo.