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S 1 :S 2 :S 3 :S 4 :S 5 :Shortly after the assassination Lee Harvey Oswald was noticed in thebook depository from which the shots had been fired.Oswald’s palm print was found on a rifle left close to the window fromwhich the shots had been fired.An eye witness identified Oswald as the assassin.According to the ballistic tests conducted, it was found that the fatalshots could have been fired from the rifle (in S 2 ).Lee Harvey Oswald assassinated President Kennedy.C: Lee Harvey Oswald assassinated President Kennedy.It is clear that the conclusion is explicitly contained in the premisses.Obviously, no one would ever present an argument of this nature. It does,however, illustrate the structure of a deductive argument and the source of itsconclusiveness. It also indicates the extent to which deductive arguments aresemantic in nature: if one were to support the premisses and deny theconclusion, one would be contradicting oneself. More interesting deductivearguments are those in which the conclusions are implicitly contained. As anexample we may use an illustration related to the previous examples:S 1 :S 2 :President Kennedy was shot by Marina Oswald’s husband.Lee Harvey Oswald was Marina Oswald’s (only) husband.Free download from www.hsrcpress.ac.zaC: President Kennedy was assassinated by Lee Harvey Oswald.The aim of the above example has been to illustrate the principle of degrees ofinductive support and the notion of adequate support. At the same time it hasbeen possible to show that inductive and deductive arguments are radicallydifferent. This difference will now be explored in a more systematic manner.Induction and deductionIt is important that we re-emphasize that in our analysis of inferences — theinferential relationship between premisses and conclusion — we are notinterested in the epistemic status (the truth or falsity) of the premisses. For thesake of our argument it is necessary that we accept that all premisses are true— in other words, that the evidence is reliable. If we accept that the premissesare true, the question that arises is how much support do they provide for theconclusion. In the Kennedy example, two possible answers to this questionwere distinguished: inductive support in which the premisses provide gradualsupport (from little to a lot) for the conclusion, or deductive111