Abstract
CONSIDER A NON EMPTY BUT OTHERWISE ARBITRARY SET OF\nPROPERTIES CALLED OBSERVATION-PROPERTIES (O-PROPERTIES).\nCALL A PROPERTY P A MEANINGFUL PROPERTY (M-PROPERTY) IF IT\nIS EQUIVALENT TO A (FINITE OR INFINITE) DISJUNCTION OF\nO-PROPERTIES--I.E., A NECESSARY AND SUFFICIENT CONDITION\nFOR P IS THAT AT LEAST ONE OBSERVATION-PROPERTY IN A\nCERTAIN SET O(P) BE TRUE. OBVIOUSLY THE CONJUNCTION AND\nDISJUNCTION OF TWO M-PROPERTIES IS AN M-PROPERTY; IN\nGENERAL THE NEGATION OF AN M-PROPERTY IS NOT AN M-PROPERTY.\nHOWEVER WE CAN DEFINE THE PSEUDO NEGATION OF AN M-PROPERTY\nP AS THE POSSESSION OF SOME O-PROPERTY INCOMPATIBLE WITH P.\nTHE ALGEBRA OF DISJUNCTION, CONJUNCTION AND PSEUDO NEGATION\nOF M-PROPERTIES TURNS OUT TO START IN THE SAME RELATION TO\nBOOLEAN ALGEBRA AS INTUITIONISTIC LOGIC (NOT 3-VALUED\nLOGIC) DOES TO CLASSICAL LOGIC, AND SUGGESTS THEREFORE THAT\nINTUITIONISTIC RATHER THAN 3-VALUED LOGIC IS THE\nAPPROPRIATE FORMALISM TO DEAL WITH THE PARADOXES OF THE\nBALD MAN, THE HEAP, ETC