What art the essential components of a logical argument?

Question

A logical argument is made up of the premise, the inference and the conclusion.The premise is the base in the structure of an argument. Within the boundaries of an argument, it isirriducible, that is, there is nothing more basic than the premise. Because the statements of the premiseare irriducible, they are also called assumptions — the reader is called upon to accept them unquestioning, for the sake of the argument — the reader has to choose not to reduce them.The inference is the set of statements derived from the premise. These statements are reducible —back to the premise.The conclusion is the final statement in the process of inference, and the statement which we are most interested in — it is like the result of an experiment. You may have been taught that an essay has topic statements — these are the conclusions that your argument is trying to reach — the goal of theexperiment, if you will.So, for example,A longer life is a good thing(premise). Science has produced medicines(premise). Medicines prolonglife(premise). Since science has produced medicines to prolong life(inference), science is a good thing(conclusion).Of course, the premise of an argument, though irriducible within that particular argument, could be the conclusion of another argument.But is longer life a good thing? Some people believe that quality is more important than duration(premise / constative statement). If a long life is wracked with suffering(premise / constative statement), then perhapslong life is not always a good thing(conclusion / normative statement).But do medicines always prolong life? etc, etc…An argument-by-assertion, therefore, occurs when an unsupported normative statement is used as thepremise to support the conclusiveness of another normative statement.Two or more unsupported statements trying to hold up one another can only end in tears.Every statement in the premise should, as far as possible, be a constative statement, or anormative statement which has been supported / made acceptable by earlier arguments orprovision of contexts.

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