This is a loose description of the Technique, more rigorous explanations will be found elsewhere, particularly at the official STAT site.
During his attempts to cure his vocal problems with the services of an eminent specialist, Frederick Matthias Alexander postulated that it must be something he was doing on stage that caused his loss of voice. He had discovered the Alexander Principle, that Use affects Function.
In his endeavours to cure himself of vocal problems performing on stage, Alexander discovered that the human being will only function at its optimum when the body is in balance and balancing. I.e. when not held fixedly in any idealised posture, but supported as freely as possible from feet to crown of head.
The relationship of head to neck; head and neck to back; head, neck and back to legs he called the Primary Control, because better co-ordination and overall functioning resulted when he was able to achieve freedom in his neck, head and back. He also found that if he could free his neck to allow his head to nod forward and go up, then the rest would follow.
This optimum functioning is total, not just relating to the musculo-skeletal system. When he had succeeded in curing his loss of voice, he noticed his general health had also improved, and that friends to whom he taught his technique also experienced improvement in their general health and with any specific problems they had.
The Technique itself is stunningly simple in concept, it comprises only two components, which F.M.A. called INHIBITION and DIRECTION.
DIRECTION may be regarded as the unforced application of mental instructions to attend to the process of changing, be that changing from one position to another, or changing the state of muscle tone in our body, or our mental attitude, provided that the change is consciously intended. Determination, trying hard, and concentration will always completely prevent progress!
INHIBITION was discovered by F.M.A. as the only way he could defeat his habit. Habit feels right, so change must feel wrong! Sensory feelings are unreliable, only thinking is dependable. Try folding your arms. Now fold them the other way (with the other arm on top). For some this is extemely difficult or impossible, for others it just feels very strange and uncomfortable. When F.M.A. felt he was putting his head forwards and up he observed in mirrors that he was, in fact, frequently doing the opposite. The solution was inhibition, to stop, say no to doing what he intended, continue to issue his directions and take a fresh and genuine decision whether to do nothing, to proceed or to do something different.
The phrase “thinking in activity” is one succinct way of describing the Technique.
However, to get to grips with the Technique, it really is necessary to have the services of a properly qualified teacher.