“There are, for approbation, certain known limits which serve as a basis for the construction of reasoning, inspired by common sense.

“It can be affirmed, in a positive way, that, if the trunk of a tree were floating easily, without sinking to the bottom of the water, it would not float the same if thirty men were to ride astride of it.

“The initial weight of the tree permits it to maintain itself on the surface; but if it be increased to an exaggerated total, we can, without hesitation, calculate indirectly the moment when it will disappear, dragging with it the imprudent men who trusted themselves to it.

“Everything in life is a question of approximation.

“The house which is built for a man will be far larger than the kennel, destined to shelter a dog, because the proportions have been calculated, by approximation, according to the relative difference between the stature of the human and canine species.

“Clothing is also suited to the temperature.

“One naturally thinks that, below a certain degree of cold, it is necessary to change light clothes for those made of thicker material.

“As with the majority of the constructive elements of common sense, approximation is always based on experience.

“It draws its conclusions from the knowledge of known limitations, whose affirmation serves as a basis for the argument which determines deduction in a most exact manner.

“Experience itself depends on memory, which permits us to recall facts and to draw our conclusions from them, on which facts reasoning is based.”

The Shogun does not fail to draw our attention to the difference between experience and experimentation.

“This last,” said he, “only serves to incite the manifestation of the first.

“It consists of determining the production of a phenomenon whose existence will aid us in establishing the underlying principles of an observation which interprets the event.

“That is what is called experience.

“Comparison is a mental operation which permits us to bring things that we desire to understand to a certain point.

“It is comparison which has divided time according to periods, which the moon follows during its entire length.

“It is by comparing their different aspects and by calculating the duration of their transformations, that men have been able to divide time as they do in all the countries of the world.

“The science of numbers is also born of comparison, which has been established between the quantities that they represent.

“This is the art of calculating the differences existing between each thing, by determining the relativeness of their respective proportions.

“Comparison acts on the mind automatically, as a rule.

“It is indispensable to the cultivation of common sense, for it furnishes the means of judging with full knowledge of all the circumstances.