CONDITIONAL SENTENCES

A simple conditional sentence

A paradigmatic English conditional sentence is:

(1) If some Canberrans vote for ABBOTT then some CANBERRANS are Liberals.

A conditional has an antecedent and a consequent. In (1) the antecedent is ‘some Canberrans vote for ABBOTT’ and the consequent is ‘some CANBERRANS are Liberals’.

In general, in any conditional of the form ‘if P then Q’, P is the antecedent and Q the consequent.

Sentence (1) would be represented in our symbolic language as:

(1a) A → C

In this formula, A is the antecedent and C the consequent.

More complicated conditional sentences

Not all English conditional sentences come neatly packaged with the antecedent between the ‘if’ and the ‘then’ and the consequent following the ‘then’. Indeed, some conditional sentences do not contain the words ‘if’ and ‘then’.

For example, consider the following sentences:

(2) MARY inherits if BILL dies.

(3) BILL dies only if MARY inherits.

(4) Only if MARY inherits, BILL dies.

(5) MARY inherits provided that BILL dies.

(6) Provided that BILL dies, MARY inherits.

(7) BILL'S dying is sufficient for MARY'S inheriting.

(8) MARY's inheriting is necessary for BILL's dying.

These sentences are, in fact, simply different ways of saying:

(9) If BILL dies, then MARY inherits.

Sentences (2)–(9) should all be represented as:

(9a) B → M