The strength and weakness of the syllogism as an instrument of reasoning will now be understood. Whately remarks, that 'since all reasoning may be resolved into syllogisms, and since in a syllogism the premises do virtually assert the conclusion, it follows at once that no new truth can be elicited by any process of reasoning.'* We therefore no longer look to the syllogism to discover truth, its value is in stating it. In this sense it is worthy of all attention. It is the form of nature.
* Logic, p. 223.
Of such a syllogism as the one quoted—
No predacious animals are ruminant,
The lion is predacious,
therefore
The lion is not ruminant.
It has been insisted by some logicians that the genius required for its construction was invention. Having made a general proposition like the first, we then have to invent or find out a middle term as the second—but if we bear in mind that the general affirmation of the first proposition relates to a class of (predacious animals in this case) objects which include the middle term, the necessity of invention is consequently dispensed with. We need only look well to what we have there. Simplicity will be promoted by returning to our previous remark, viz.—that reasoning is asserting a proposition, and then showing why it is true—in other words, adducing the fact or facts, on which the assertion rests.
In the Logic given in 'Chambers' Information,' it is said—' In choosing your middle terms, or arguments to prove any question, always take such topics as are purest and least fallible, and which carry the greatest evidence and strength with them,' But it rather appears that we have not to invent a middle term, but only to look to the major premises, and find it included there.
By methodical questioning any argument may be tested. Thus, on any assertion being made, ask—Why is the assertion true? In this manner, if an argument has truth in it, it may be elicited. In this manner you dig through assertions down to premises, and discover whether any ore of truth lies there.
The value of the argument depends upon the final answer which reveals the premises or data of facts, upon which the conclusion rests. Forms of speech, classification of propositions, figures of syllogisms, are of minor importance when you have once elicited the rough truth. The best test of an argument is the soundness of its data, and the simplest formula for drawing out and exhibiting such data, is of the greatest service in enabling us to judge of the validity thereof.