Conditional syllogism

Disciplines > Argument > Syllogisms > Conditional syllogism

Description | Example | Discussion | See also

Description

The basic form of the conditional syllogism is: If A is true then B is also true. (If A then B). It appears through a major premise, a minor premise and a conclusion.

Major premise

The major premise (the first statement) for example:

Ladies prefer Xanthos.

This statement is not challenged and is assumed to be true.

The 'A', the 'if' part of the statement ('adding sugar to coffee' in the example) is also called the antecedent. The 'B', the 'then' part of the statement ('tastes better') is also called the consequent.

Minor premise

A minor premise, which may not be spoken, gives further detail about the major premise. For example:

Xanthos smells great.

The minor premise is also assumed to be true. In adverts, it often appears as the secondary line to the main strapline of the major premise.

Conclusion

The conclusion is a third statement, based on a combination of the major and minor premise.

If you use Xanthos cologne, you will attract women.

In adverts, this may well not be mentioned, but it is most clearly what you are intended to conclude.

Example

Here is the bones of many the proposition of many therapists:

You are sad.
I am qualified to help people who are sad.
I can make you happy.

Thus, when the therapist says 'You are sad', the patient gets the idea that the therapist can make them happy. The qualifications of the therapist may be framed on the wall or on the brass plate outside. This principle is also used by many professions, which is why it is ok for hairdresser to criticize your hair (in fact it provides a contrast with what your hair will soon look like).

Discussion

Conditional syllogisms are seldom completed with all three sentences -- often only the major and minor premises are needed and sometimes only the major premise is enough.

The conclusion of the conditional syllogism is often unspoken and it is intended that the listener infers it for themselves.

Advertisers love conditional syllogisms because this gives them a way around laws that prevent advertisements from telling direct lies. Lies such as 'use cologne, attract women' are also a bit obvious, and people who will believe the syllogism would not necessary believe the direct lie of the conclusion.