_Antecedents._ _Consequents._ A B C D ―― P₁ A D E F ―― P₂ A L M N ―― P₃ A O P Q ―― P₄ Second statement. P₁ ―― A B C D P₂ ―― A D E F P₃ ―― A L M N P₄ ―― A O P Q In the first case, the sole invariable antecedent is A, and, therefore, we infer that A is probably the cause of P. In the second case, the invariable consequent being A, is probably the effect of P. (3) Concrete examples illustrating first statement. _The Problem_: Cause of John’s tardiness. On investigation the various _antecedents_ are these: (1) John has his breakfast at _seven_; (2) after breakfast he carries his father’s _dinner_ to him and (3) feeds the hens; and then (4) goes to school by the _path through the woods and around the mill pond_. _Phenomenon as a consequent._ John is tardy. Determining to do away with the tardiness, the teacher brings about a variation in the antecedents, varying _one at a time_ taken in the order indicated above. To wit: (1) Varying the first antecedent. John breakfasts at 6:30; Other antecedents the same; (_Phenomenon_) But John is tardy. (2) Varying the second antecedent. The younger brother carries the dinner; Other antecedents the same; (_Phenomenon_) John is tardy. (3) Varying the third antecedent. Another brother cares for the hens; Other antecedents the same; (_Phenomenon_) John is still tardy. The teacher is now quite certain that the tardiness is due to the route through the woods and around the pond. Using, as symbols, the initial letters of the italicized “key-words” of the antecedents as stated above, the case of tardiness may be symbolized as follows: _Key words_ _Symbols_ seven s dinner d hens h woods w tardy t₁, t₂, t₃ _Antecedents_ _Phenomenon_ s d h w t₁ e d h w t₂ s b h w t₃ s d a w t₄ “w” standing for route through the woods, is seen to be the invariable antecedent. (4) Concrete example illustrating the second statement. _The Problem_: To determine the effect of direct primaries. _First trial._ _Antecedent_ _Consequents_ { 1. Greater expense to candidate, Direct { 2. Greater interest shown, primary { 3. Better men nominated, { 4. “Bumper” crops. _Second trial._ { 1. Greater expense to candidate, Direct { 2. Greater interest shown, primary { 3. Better men nominated, { 4. Crops below average. _Third trial._ { 1. No greater expense, Direct { 2. Greater interest shown, primary { 3. Better men nominated, { 4. Crops average. _Fourth trial._