238 THE MONTESSORI METHOD
telligent and cultured guides, not losing ourselves in vain discourse, but illustrating briefly and concisely the work of art in which the traveller shows himself interested, and we should then respectfully allow him to observe it as long as he wishes to. It is our privilege to lead him to observe the most important and the most beautiful things of life in such a way that he does not lose energy and time in useless things, but shall find pleasure and satisfaction throughout his pilgrimage.
I have already referred to the prejudice that it is more suitable to present the gRometric forms to the child in the solid rather than in the plane, giving him, for example, the cube, the sphere, the prism. Let us put aside the physiological side of the question showing that the visual recognition of the solid figure is more complex than that of the plane, and let us view the question only from the more purely pedagogical standpoint of practical life.
The greater number of objects which we look upon every day present more nearly the aspect of our plane gRometric insets. In fact, doors, window-frames, framed pictures, the wooden or marble top of a table, are indeed solid objects, but with one of the dimensions greatly reduced, and with the two dimensions determining the form of the plane surface made most evident.
When the plane form prevails, we say that the window is rectangular, the picture frame oval, this table square, etc. Solids having a determined form prevailing in the plane surface are almost the only ones which come to our notice. And such solids are clearly represented by our plane gRometric insets.
The child will very often recognise in his environment forms which he has learned in this way, but he will rarely recognise the solid gRometric forms.