In incomplete absolute identity the subject is identical with the predicate in meaning only. Illustrated by definitions. In relative identity the whole of the subject may be affirmed of a part of the predicate or a part of the subject may be affirmed of a part of the predicate. (3) “It is impossible for the same thing to be itself and its contradictory at the same time,” is a statement of the law of contradiction. _Identity_ is _con_structive while _contradiction_ is _de_structive in nature. To make the proposition negative the word _not_ must be used with the copula. “_Not_” attached to the predicate with a hyphen makes the _predicate_ negative, but not the _proposition_. To use opposite terms in a contradictory sense leads to serious error. The safest way of making a positive term a contradictory negative term is to prefix “_not_” with a hyphen or use “non.” (4) The law of excluded middle is virtually a combination of identity and contradiction. It may be stated as follows: “A thing must either be itself or its contradictory.” (5) “Every condition must have a sufficient reason for its existence,” is the law of sufficient reason. Its distinct province is physical science rather than logic. (6) The laws may be expressed mathematically: excluded middle = identity + contradiction. SCHEMATIC STATEMENT OF PRIMARY LAWS. ┌───────────┬───────────────────┬────────────────┬────────────────────┐ │ Name │ Stated │ Symbolized │ Illustrated │ ├───────────┼───────────────────┼────────────────┼────────────────────┤ │ Absolute │ Whatever is, is │ A is A │ Work is work │ │ identity │ │ │ │ ├───────────┼───────────────────┼────────────────┼────────────────────┤ │ Relative │ The whole is │ All A is B │ Work is a blessing │ │ identity │ identical with │ Some A is B │ Some play is a │ │ │ a part or a part │ │ blessing │ │ │ is identical │ │ │ │ │ with a part │ │ │ ├───────────┼───────────────────┼────────────────┼────────────────────┤ │ Contra- │ Nothing can both │ A is not not-A │ Work is not │ │ diction │ be and not be at │ or │ not-work │ │ │ the same time │ A is not B │ John is not honest │ │ │ │ or │ Albert is not │ │ │ │ A is not not-B │ not-honest │ ├───────────┼───────────────────┼────────────────┼────────────────────┤ │ Excluded │ Everything must │ A is either A │ Fair play is │ │ middle │ either be or not │ or not-A │ either fair play │ │ │ be │ or │ or not-fair play │ │ │ │ A is either B │ This man is either │