#51.# The second principle is equally important: #There is a natural order in which the powers of the soul should be exercised.# This order is the order of their activity. The earliest power to become educationally active is sensation, the last is reason, and hence we can phrase this law in the maxim "from sense to reason." Different writers state the same thing in the following way: observation before reasoning; the concrete before the abstract; sense knowledge before thought knowledge; facts before definitions; processes before rules; the particular before the general; the simple before the complex; from the known to the next related unknown. All these maxims may be traced to the same law of the soul, and they may all be summed up in the maxim, _teaching must proceed from things to symbols_, since the senses deal with things and reason deals with symbols. No wise teacher will pass this law by until its full significance is understood. Jesus was a masterful teacher. He observed this law frequently. Note the examples in the Gospels, using the incident at Jacob's well as an example. Æsop's fables are all built upon the principle here laid down, as are the numerous fairy tales by the Grimms, Andersen, and others. #52.# Since the soul grows only by its own activity a third law arises: #Knowledge can be acquired only by occasioning the proper activity in the soul of the pupil.# It is always important to keep in mind that it is not what the teacher thinks and does, but what he causes the pupil to think and do, that makes for knowledge. The best teaching secures the best mental activity on the part of the pupil. #53.# Just what the proper activity is may be seen by a consideration of a fourth principle: #First presentations of new knowledge must be made objectively in all grades of the school.# Ideas cannot be taught through words. They can be taught through objects, and the ideas can then be named. The name is the word. This law may be stated as "ideas before words." It stands as a protest against abstract and formal teaching. It demands that knowledge shall be fitted to the nature of the soul's growth. The child that for the first time was shown a growing fern in a vase and called it "a pot of green feathers" was on the right track. He will in due time acquire the right word. His idea is clear. It follows also that _the only words in which knowledge can be presented to the soul are words that name known things_.