184: THE MONTESSORI METHOD
distribution of the stimuli. This will be treated more fully in the description of the didactic system (materials) and of the sense education. Here it is enough to say that one should proceed from few stimuli strongly contrasting, to many stimuli in gradual differentiation always more fine and imperceptible. So, for example, we first present, together, red and blue; the shortest rod beside the longest; the thinnest beside the thickest, etc., passing from these to the delicately differing tints, and to the discrimination of very slight differences in length and size.