four valued logic

The disjunction

Disjunction of four valued logic is defined for the same generation rule as Disjunction of 2-valued logic.

But this disjunction has considerably different and complex shape compared with that of 2-valued logic.

It is important in law or science that the 3rd valued proposition is disjunctive to the 1st valued proposition,

because its disjunction has the 3rd truth value.

Especially, for logic of Buddhism, it is important that 4th valued proposition is disjunctive to the 1st valued proposition,

because its disjunction has the 4th truth value.

This is most important and useful logical rule for our communication.