Download Logical Fallacies

Logical Fallacies
Logical fallacies are often used as propaganda techniques. Unfortunately, our lives are
filled with lies. Advertisements lie. Politicians lie. Scandalous corporate executives lie.
Well, you might say, this is their problem. True. True. BUT, it becomes our problem
when we cannot distinguish truth from fallacy. Ah, fallacy. We come to our point. In
order to write effective arguments for the A.P. exam, we must be wary of logical
fallacies. (We must also be able to spot these fallacies in written and spoken arguments
to ensure we do not become mindless sheep, but I digress.) On with the assignment…
1. Ad hominem: (to the man) “Any argument that attempts to counter another’s
claims or conclusions by attacking the person, rather than addressing the
argument itself.”
Example: If you believe in UFOs, you are crazy.
2. Non sequitur: (does not follow) “An argument in which the conclusion does not
necessarily follow the premises…a logical connection is implied where none
exists.”
Example: The apartment builder he lives in is enormous; his apartment must be
spacious.
3. Post-hoc ergo propter hoc: (after this, therefore because of this) Often called
“Post hoc.” “A proceeded B, therefore A caused B, and therefore assumes cause
and effect.”
Example: “President Jones raised taxes, and then the rate of violent crime went up.
Jones is responsible for the rise in crime”
4. Slippery Slope: “The arguer claims that a sort of chain reaction, usually ending in
some dire consequence, will take place, but there’s really not enough evidence for
that assumption. The arguer asserts that if we take even on step into the slippery
slope, we will end up sliding all the way to the bottom.”
Example: “Animal experimentation reduces our respect for life. If we don’t respect
life, we are likely to be more and more tolerant of violent acts like war and murder.
Soon our society will become a battlefield in which everyone constantly fears for
their lives.”
5. Red Herring: “Partway through an argument, the arguer goes off on a tangent,
raising a side issue that distracts the audience from what’s really at stake. Often
the arguer never returns to the original issue.”
Example: “Grading this exam on a curve would be the most fair thing to do. After
all, classes go more smoothly when the students and the professor are getting along
well.”
6. Begging the Question: “To assume a conclusion in one’s question….”
“Asks the reader to accept the conclusion without providing real evidence; the
argument either relies on the premise that says the same thing as the conclusion…or
simply ignores an important assumption that the argument rests on…”
Example: “Active euthanasia is morally acceptable. It is a decent, ethical thing to
help another human being escape suffering through death.”
Sources:
The Writing Center at UNC-Chapel Hill
The Skeptic’s Guide to the Universe
Purdue Owl Logical Fallacies