What are the core principles that all natural horsemanship trainers share?

Despite the significant differences in method, style, and emphasis between trainers as varied as Tom Dorrance, Pat Parelli, Clinton Anderson, and Warwick Schiller, a set of core principles runs through virtually all approaches that identify as natural horsemanship. The most fundamental is that horses learn through pressure and release — that the correct response is taught by applying pressure that motivates the horse to search for a change, and that releasing that pressure at the exact moment the horse offers the correct response is what teaches the horse what the desired behavior is. Related to this is the principle that timing is everything: a release that comes too late teaches the wrong lesson, while a release that comes precisely at the moment of the correct response teaches the right one. Reading the horse's body language and emotional state — understanding whether the horse is in a thinking, learning state or a flight-aroused survival state — is another principle shared across all natural horsemanship traditions, because training that pushes the horse past its threshold into a flight response is not effective training regardless of the method used. The importance of the horse's trust and willingness — seeking cooperation rather than coercion — is a philosophical principle that unites the entire tradition even when trainers differ substantially on how that trust is built. Working from the ground before the saddle, developing the horse's understanding of yield-to-pressure concepts in a lower-demand environment before adding the complexity of a rider, is a practical application of these principles that most natural horsemanship traditions share. And the concept of reward through release — that the horse is never seeking the pressure but always seeking the release from it — is the learning-theory foundation that all effective pressure-and-release training is built on.