58. Mediums write under the influence of the spirits who use them, as their instruments; their hand is caused to write by involuntary movement, which most of the time they cannot control. Some mediums have no awareness ofwhat they are writing; others are vaguely aware, although the thought is not their own. This is what distinguishes the mechanical, intuitive and semi-mechanical mediums. Spiritist science explains the way the spirit's thought is transmitted to the medium and the role the latter plays in communications.