On one hand, it is the culmination of the equestrian literature of the late 18th century and 19th century that, under the influence of the Industrial Revolution, tried to explain equine biomechanics by comparing the body to a mechanical device.
On the other hand, it forms the theoretical foundation for the H. Dv. 12 German Cavalry Manual on the training of horse and rider [Xenophon Press 2014] and its successor, the Richtlinien fuer Reiten und Fahren of the German National Federation. The Gymnasium of the Horse belongs on every dressage rider's bookshelf. It's the kind of book that needs to be studied, because every word is chosen deliberately, and every sentence is full of knowledge and meaning. It's a book that needs to be re-read regularly, because with each new reading, your understanding will evolve and deepen.
It is a true classic, because it is universally accepted and admired, not only in Germany, but also in the rest of the dressage world, as it contains so much wisdom, so much invaluable advice that even 130 years later, it has lost nothing of its relevance. Steinbrecht formulates rules, principles, and guidelines for horse training more concisely and more sharply than almost any other author. His book has truly stood the test of time.