Thought-Culture; Or, Practical Mental Training

by William Walker Atkinson

2. If "E" is true; show what follows for A, I and O. Also what follows if "E" be false.

3. If "I" is true; show what follows for A, E and O. Also what follows if "I" be false.

4. If "O" is true; show what follows for A, E and I. Also what happens if "O" be false.

CONVERSION OF JUDGMENTS

Judgments are capable of the process of Conversion, or the change of place of subject and predicate. Hyslop says: "Conversion is the transposition of subject and predicate, or the process of immediate inference by which we can infer from a given preposition another having the predicate of the original for its subject, and the subject of the original for its predicate." The process of converting a proposition seems simple at first thought but a little consideration will show that there are many difficulties in the way. For instance, while it is a true judgment that "All horses are animals," it is not a correct Derived Judgment or Inference that "All animals are horses." The same is true of the possible conversion of the judgment "All biscuit is bread" into that of "All bread is biscuit." There are certain rules to be observed in Conversion, as we shall see in a moment.

The Subject of a judgment is, of course, the term of which something is affirmed; and the Predicate is the term expressing that which is affirmed of the Subject. The Predicate is really an expression of an attribute of the Subject. Thus when we say "All horses are animals" we express the idea that all horses possess the attribute of "animality;" or when we say that "Some men are artists," we express the idea that some men possess the attributes or qualities included in the concept "artist." In Conversion, the original judgment is called the Convertend; and the new form of judgment, resulting from the conversion, is called the Converse. Remember these terms, please.

The two Rules of Conversion, stated in simple form, are as follows:

I. Do not change the quality of a judgment. The quality of the converse must remain the same as that of the convertend.

II. Do not distribute an undistributed term. No term must be distributed in the converse which is not distributed in the convertend.

The reason of these rules is that it would be contrary to truth and logic to give to a converted judgment a higher degree of quality and quantity than is found in the original judgment. To do so would be to attempt to make "twice 2" more than "2 plus 2."