The prolix discourses of systems must be interrupted: 'All theory is always silent or vanishes at the patient's bedside';'` and the suggestions of the imagination which anticipate what one perceives, find illusory relations, and give voice to what is inaccessible to the senses must also be reduced: 'How rare is the accomplished observer who knows how to await, in the silence of the imagination, in the calm of the mind, and before forming his judgement, the relation of a sense actually being exercised!''