CaveatSometimes an argument does not explicitly state all its premises or even its conclusion.

Consider these two arguments:

Every person has a right to life, so the fetus has a right to life.

All philosophy professors are jerks, and he’s a philosophy professor, so he’s a jerk. vs.

The first one can be re-written like this:

All philosophy professors are jerks.

He is a philosophy professor.

So he is a jerk.

The second one can be re-written like

this:

[The fetus is a person.]Every person has a right to life.So the fetus has a right to life.

EnthymemeAn argument that is stated incompletely, part being “understood” or only “in the mind.”

SamplesIdentify the missing premise or conclusion or each argument.

All hamsters are turtles, so all hamsters are reptiles.

Children should have rights because children are people, too.

Good poets aren’t good critics, because good poets aren’t bitter.

Something can exist only if it is a material thing. Ghosts have no substance.

Messing with Chris’s women is trouble, so I know I’m in trouble now.

Kobe Bryant should be the Most Valuable Player for 2005-06, because he scored more points than any other player.

The barometer is falling sharply, so the weather is going to change.

Exercisesa. Identify what part is missing (premise or conclusion)b. Supply the missing part.

A nation without a conscience is a nation without a soul. A nation without a soul is a nation that cannot live.

Children shouldn’t have rights because they have no responsibilities.

Communism is opposed by reform liberals precisely because it violates individual freedom.

Communism, simply because it is a godless philosophy, contains within itself the seeds of its own destruction.

Everyone who hates his brother is a murderer. And you know that no murderer has eternal life in him.

He would not take the crown; therefore ‘tis certain he was not ambitious.

Small countries tend to remember history especially well, since it often turns out badly for them.

The human soul is spiritual, and whatever is spiritual is immortal.

The open shop is good for unions because it makes them more democratic.

The open shop is good for unions because it makes them more democratic.

Tomato prices will go up, since farmers were hit by a hard freeze last week.

The roof is leaking. So it must have snowed.