Some instructors of baby logic define an enthymeme as an argument with at least one missing premise. Strictly speaking this is a mistake. If the premise is needed to render the argument valid, and yet it’s missing, then the argument will be invalid. So by this definition every enthymematic argument is invalid. But that’s not what we want out of the concept. So an enthymeme should be defined as an argument with at least one unstated – sometimes called a ‘suppressed’ – premise. Usually the premise goes unstated because it’s taken by the speaker to be either too self-evident, or else too assuredly shared by speaker and listener alike, to warrant articulation.

More often than not enthymematic argumentation is harmless. But sometimes not. Consider:

1) The foetus is a person.
2) Abortion kills a person. So
4) One ought not to have an abortion.

The debate will typically focus on (1), i.e. the metaphysical claim. But what’s being suppressed – because it’s being assumed – is the moral claim that

3) It’s wrong to kill a person.

This is not to say the disputants couldn’t focus on (1) because they do both subscribe to (3). It’s to say only that the very act of articulating (3) might fruitfully put it back on the table.

I mention this not because I have a view about abortion. (I do, but as my readers know, it hangs on the race of the foetus.) Rather I mention this because the resolution of so many of today’s hot button issues is blocked by this kind of enthymematic argumentation. Here are just some of the things that may well be true but shouldn’t be assumed.

• If it’s my body it’s my property, and
• if it’s my property I have the right to dispose of it.
• If it’s a person it’s a rights-bearer.
• If God created it, it’s His property, and
• if it’s His property He has the right to dispose of it.

I could go on. And elsewhere I have. But even this sample should suffice to raise serious doubts about the self-evidence of the right to end one’s life or the incumbency of divine command.

As it happens I don’t think your life belongs to you, at least not categorically. As it happens I think my druthers trump yours. But I don’t think God’s druthers trump either of ours. I could be wrong. But if so it’s not because – if I’m allowed a rather stretched metaphor – I left some stone unturned.

Categories: Critical Thinking, pure philosophy, Social and Political Philosophy

Tags: abortion, metaphysics, morality, property, rights