§ 26. Again, as Nature does nothing _per saltum_, nor halts when she has begun, the whole course of studies should be arranged in strict order, so that the earlier studies prepare the way for the later. Every year, every month, every day and hour even, should have its task marked out beforehand, and the plan should be rigidly carried out. Much loss is occasioned by absence of boys from school, and by changes in the instruction. Iron that might be wrought with one heating should not be allowed to get cold, and be heated over and over again. § 27. Nature protects her work from injurious influences, so boys should be kept from injurious companionships and books. § 28. In a chapter devoted to the principles of easy teaching, Comenius lays down, among rules similar to the foregoing, that children will learn if they are taught only what they have a desire to learn, with due regard to their age and the method of instruction, and especially when everything is first taught by means of the senses. On this point Comenius laid great stress, and he was the first who did so. Education should proceed, he said, in the following order: first, educate the senses, then the memory, then the intellect; last of all the critical faculty. This is the order of Nature. The child first perceives through the senses. “_Nihil est in intellectu quod non prius fuerit in sensu._ Everything in the intellect must have come through the senses.” These perceptions are stored in the memory, and called up by the imagination.[71] By comparing one with another, the understanding forms general ideas, and at length the judgment decides between the false and the true. By keeping to this order, Comenius believed it would be possible to make learning entirely pleasant to the pupils, however young. Here Comenius went even further than the Jesuits. They wished to make learning pleasant, but despaired of doing this except by external influences, emulation and the like. Comenius did not neglect external means to make the road to learning agreeable. Like the Jesuits, he would have short school-hours, and would make great use of praise and blame, but he did not depend, as they did almost exclusively, on emulation. He would have the desire of learning fostered in every possible way—by parents, by teachers, by school buildings and apparatus, by the subjects themselves, by the method of teaching them, and lastly, by the public authorities. (1) The parents must praise learning and learned men, must show children beautiful books, &c., must treat the teachers with great respect. (2) The teacher must be kind and fatherly, he must distribute praise and reward, and must always, where it is possible, give the children something to look at. (3) The school buildings must be light, airy, and cheerful, and well furnished with apparatus, as pictures, maps, models, collections of specimens. (4) The subjects taught must not be too hard for the learner’s comprehension,