Still, animals and men are moving bodies; and it is recognised that their thoughts and feelings are so connected with their movements and with the movements of other things acting upon them, that we can judge of one case by another; although the connection is by no means well understood, and the best words (such as all can agree to use) have not yet been found to express even what we know about it.  Hence, a regular connection being granted, I have not hesitated, to use biological and social events and the laws of them, to illustrate causation and induction; because, though less exact than chemical or mechanical examples, they are to most people more familiar and interesting.

In practical affairs, it is felt that everything depends upon causation; how to play the fiddle, or sail a yacht, or get one’s living, or defeat the enemy.  The price of pig-iron six months hence, the prospects of the harvest, the issue in a Coroner’s Court, Home Rule and Socialism, are all questions of causation.  But, in such cases, the conception of a cause is rarely applied in its full scientific acceptation, as the unconditional antecedent, or ‘all the conditions’ (neither more nor less) upon which the event depends.  This is not because men of affairs are bad logicians, or incapable of scientific comprehension; for very often the reverse is conspicuously true; but because practical affairs call for promptitude and a decisive seizing upon what is predominantly important.  How learn to play the fiddle?  “Go to a good teacher.” (Then, beginning young enough, with natural aptitude and great diligence, all may be well.) How defeat the enemy?  “Be two to one at the critical juncture.” (Then, if the men are brave, disciplined, well armed and well fed, there is a good chance of victory.) Will the price of iron improve?  “Yes:  for the market is oversold”:  (that is, many have sold iron who have none to deliver, and must at some time buy it back; and that will put up the price—­if the stock is not too great, if the demand does not fall off, and if those who have bought what they cannot pay for are not in the meanwhile obliged to sell.) These prompt and decisive judgments (with the parenthetic considerations unexpressed) as to what is the Cause, or predominantly important condition, of any event, are not as good as a scientific estimate of all the conditions, when this can be obtained; but, when time is short, the insight of trained sagacity may be much better than an imperfect theoretical treatment of such problems.

Sec. 4.  To regard the Effect of certain antecedents in a narrow selective way, is another common mistake.  In the full scientific conception of an Effect it is the sum of the unconditional consequences of a given state and process of things:  the consequences immediately flowing from that situation without further conditions.  Always to take account of all the consequences of any cause would no doubt be impracticable; still the practical, as well as the scientific interest,