"Too many people," said he, "wish to undertake to make deductions by eliminating the elements which deprive them of a desired decision.
"They do not fail either to exaggerate the reasons which plead in favor of this decision; also we see many persons suffer from reasoning, instead of feeling the good effects of it."
Those who cultivate common sense will never fall into this error, for they will have no difficulty in convincing themselves that by acting thus they do not deceive any one except themselves.
By glossing over truth in order to weaken the logical consequences of deductions they are the first to be the victims of this childish trick.
That which is called false deduction is rarely aught save the desire to escape a resolution which a just appraisement would not fail to dictate.
It might be, also, that this twisting of judgment comes from a person having been, in some past time, subjected to unfortunate influences.
By devoting oneself to the evolution of thought, of which we have already spoken when presenting the symbolical fan, and above all, by adopting the precepts which, following the method of Yoritomo, we are going to develop in the following lessons, we shall certainly succeed in checking the errors of false reasoning.
"The important thing," said he, "is not to let wander the thought, which, after resting for a moment on the subject with which we are concerned and after touching lightly on ideas of a similar character, begins to stray very far from its basic principles.
"Have you noted the flight of certain birds?
"They commence by gathering at one point, then they describe a series of circles around this point, at first very small, but whose circumference enlarges at every sweep.
"Little by little the central point is abandoned, they no longer approach it, and disappear in the sky, drawn by their fancy toward another point which they will leave very soon.
"The thoughts of one who does not know how to gather them together and to concentrate them are like these birds.
"They start from a central point, then spread out, at first without getting far from this center, but soon they lose sight of it and fly toward a totally different subject that a mental representation has just produced.
"And this lasts until the moment when, in a sudden movement, the first one is conscious of this wandering tendency.
"But it is often too late to bring back these wanderers to the initial idea, for, in the course of their circuits, they have brushed against a hundred others, which are confounded with the first, weaken it, and take away its exact proportions.
"The great stumbling-block again is that of becoming lost in the details whose multiplicity prevents us from discerning their complete function in the act of practising deduction.
"It is better, in the case where our perception finds itself assailed by the multitude of these details, to proceed by the process of elimination, in order not to become involved in useless and lazy efforts.
"In this case we must act like a man who must determine the color of a material at a distance where the tiny designs stand out in a relief of white on a background of black.
"Suppose that he is placed at a distance too great to perceive this detail.
"What should he do to be able to give the best possible description?
"He will proceed by elimination.
"The material is neither red nor green; orange and violet must be set aside, as well as all the subordinate shades.
"It has a dull appearance, hence, it is gray; unless.... And here mental activity comes into play and will suggest to him that gray is composed of black and white.
"He will then be sure to form a judgment which will not be spoiled by falsity, if he declares that the material is a mixture of black and white.
"Later, by drawing nearer, he will be able to analyze the designs and to convince himself of their respective form and color, but by deducing that the material was made up of the mixture of two colors he will have come as near as possible to the truth:
"Deduction never prejudges; it is based on facts; only on things accomplished; it unfolds the teaching that we ought to obtain as a result."
Again the Shogun recommends to us the union of thoughts and the continuous examination of past incidents in the practise of deductions.
"If on entering a room," said he, "we are at times confused, it happens also that we correct this impression after a more attentive examination.
"The gilding is of inferior quality; the materials are of cotton, the paintings ordinary, and the mattings coarse.
"At first sight we should have deduced, judging from appearances, that the possessor of this house was a very rich man, but a second examination will cause us to discover embarrassment and anxiety.
"It is the same with all decisions that we must make.
"Before devoting ourselves to deductions inspired by the general aspect of things, it is well to examine them one by one and to discover their defects or recognize their good qualities.
"We shall be able thus to acquire that penetration of mind whose development, by leading us toward wise deductions, will bring us to the discovery of the truth."
LESSON VIII
HOW TO ACQUIRE COMMON SENSE
Common Sense is a science, whatever may be said; according to Yoritomo, it does not blossom naturally in the minds of men; it demands cultivation, and the art of reasoning is acquired like all the faculties which go to make up moral equilibrium.
"This quality," said the philosopher, "is obscure and intangible, like the air we breathe.
"Like the air we breathe, it is necessary to our existence, it surrounds us, envelops us, and is indispensable to the harmony of our mental life.
"To acquire this precious gift, many conditions are obligatory, the principle ones being:
"Sincerity of perception.
"Art of the situation.
"Attention.
"Approximation.
"Experience.
"Comparison.
"Analysis.
"Synthesis.
"Destination.