A set of five independent postulates for Boolean algebras, with application to logical constants

Postulate-sets for determining the class of Boolean algebrasf have been given by Schröder,^ Whttehead,§ and Huntington.|| Schroder's set of ten postulates assumes—in addition to an undefined class K, common to all these postulate-sets—an undefined dyadic relation, 4 > and Boole's 1f undefined binary AT-rules** of combination, + and X ; Whitehead's two sets, the first of thirteen, and the second of fifteen, postulates, and Huntington's first set, of ten postulates, assume the same undefined AT-rules of combination, + and X , which Huntington writes respectively © and o ; Huntington's second set, of nine postulates, assumes Schroder's undefined relation 4 >