Sometimes an argument does
not explicitly state all its
premises or even its
conclusion.
Consider these two arguments:
All philosophy professors are
jerks, and he’s a philosophy
professor, so he’s a jerk.
vs.
Every person has a right to life,
so the fetus has a right to life.
The first one can be re-written
like this:
He is a philosophy professor.
All philosophy professors are
jerks.
So he is a jerk.
The second one can be rewritten like this:
Every person has a right to life.
[The fetus is a person.]
So the fetus has a right to life.
An argument that is stated
incompletely, part being
“understood” or only “in the
mind.”
Identify 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.
a. 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.