SHORTER TRUTH TABLE METHOD OR REDUCTIO-AD-ABSURDUM A PRESENTATION BY DR. BUDUL CHANDRA DAS. ASSISTANT PROFESSOR OF PHILOSOPHY WOMEN’S COLLEGE, TINSUKIA TINSUKIA – 786125 ASSAM bcd.wc.tsk@gmail.com

SHORTER TRUTH TABLE METHOD OR REDUCTIO-AD-ABSURDUM LET US CONSIDER THE FOLLOWING ARGUMENT- FORM: p q q r Therefore, p r ∩ ∩ ∩ -This argument may be converted to a truth functional expression as: (p q) . (q r) } (p r) ∩ ∩ ∩ ∩ THERE ARISES A CONTRADICTION NOW LOOK AT THE GREEN OVAL FUNCTION T T T F F T T T T F F NOW, AN IMPLICATIVE FUNCTION BECOMES FALSE WHEN THE ANTECEDENT IS TRUE AND THE CONSEQUENCE IS FALSE. THUS… NOW, A CONJUNCTIVE FUNCTION WILL BE TRUE IF BOTH THE CONJUNCTS ARE TRUE. THUS THE VALUES FOR BOTH THE IMPLICATIVE FUNCTIONS OF THE FIRST PART WILL BE TRUE. i.e. ANTECEDENT CONSEQUENT MAIN CONSTANT THIS CONTRADICTION MEANS OUR ORIGINAL ASSUMPTION IS WRONG,SO THE ARGUMENT IS VALID. CONSIDER IT AS FALSE & PUT A F FOR THIS CONSTANT THEN FOLLOWING THE SAME METHOD IN CACE OF THE VARIABLES WE HAVE AS SHOWN…

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