3. Therefore the protective tariff should be abolished.
Each of the above syllogisms stands as an argument for the abolition of the protective tariff; or, to take the standpoint of the proposition each supports the contention that the tariff should be imposed for revenue only. All of the five reasons lead to a single conclusion. We may represent this relation by the following diagram:
This use of deductions is very simple, but in dealing with a combination of induction and deduction the process may become very complicated. For example, the major premise of the first syllogism above stated has back of it another logical process of reasoning. Why should all things which encourage the formation of trusts be abolished? What proof can we show to establish the conclusion (in A, the major premise) that the formation of trusts should be discouraged rather than encouraged? It must be established in a logical manner. We may establish it by induction by showing that each one of a large number of trusts has had injurious effects. After we have introduced positive evidence establishing a perfect or an imperfect induction we have laid a sufficiently strong foundation for the deductive syllogism.
On the other hand, we may establish the major premise of the above syllogism by means of deduction. To do this we might find evidence which would prove that trusts increase the cost of producing commodities and decrease their quality. In this case it would be necessary to introduce evidence only along the line which would show that this evil was characteristic of all trusts. This would be an induction, because the general principle used as a major premise would be based upon specific instances. Beginning with this induction we would build up the following syllogism, the conclusion of which supports the major premise of the foregoing syllogism.
1. All forms of business organization which increase the cost of producing commodities and decrease their quality are an industrial evil.
2. The trust is a form of business organization which increases the cost of production and decreases the quality of commodities.
3. Therefore the trust is an industrial evil.
Then to continue our deductive reasoning we would construct the following syllogism based upon the foregoing:
1. All industrial evils should be discouraged.