Conditionals
Conditionals have the form “If , then .” What goes in the first blank of this pattern is called the antecedent of the conditional; what goes in the second blank is called its consequent. Sometimes conditionals appear in the indicative mood:
If it rains, then the crop will be saved.
Sometimes they occur in the subjunctive mood:
If it had rained, then the crop would have been saved.
There are also conditional imperatives:
If a fire breaks out, then call the fire department first!
And there are conditional promises:
If you get into trouble, then I promise to help you.
Indeed, conditionals get a great deal of use in our language, often in argu- ments. It is important, therefore, to understand them.
Unfortunately, there is no general agreement among experts concerning the correct way to analyze conditionals. We will simplify matters and avoid some of these controversies by considering only indicative conditionals. We will not examine conditional imperatives, conditional promises, or subjunc- tive conditionals. Furthermore, at the start, we will examine only what we will call propositional conditionals. We get a propositional conditional by sub- stituting indicative sentences that express propositions—something either true or false—into the schema “If , then .” Or, to use technical language already introduced, a propositional conditional is a substitution instance of “If p, then q” in which “p” and “q” are propositional variables. Of the four conditional sentences listed above, only the first is clearly a propo- sitional conditional.
