Logical fallacies are errors in reasoning that invalidate arguments. Some common logical fallacies include ad hominem, which attacks the person rather than the issue; false dilemma, which only presents two alternatives when more exist; false analogy, which draws comparisons between dissimilar things; and slippery slope, which claims a small step will lead to disastrous consequences. Logical fallacies should be avoided in philosophical reasoning and debate.

1. Logical Fallacies

2. What is a logical fallacy?
Errors in reasoning that invalidate
the argument.

4. Ad Hominem – “Argument
against the man”
• Unfairly attacking a person instead of the
issue
• Attacking the character and/or reputation
of a position’s supporters; “Guilt by
association”
Example: We cannot listen
to Miss MacLachlan’s
opinion on hip-hop
because she loves Taylor
Swift.

5. Remember chain emails?

6. False Dilemma
• Either or Fallacy
• Discussing an issue as if there are only
two alternatives
• This fallacy ignores any other possible
alternatives
Example: We either ban Justin Bieber or
the world will end.

8. False Analogy
• Making a comparison between two
subjects that have more dissimilarities
than similarities.
Example: Taking Philosophy at Nat 5/Higher
is like taking away your social life.

10. Post Hoc, Ergo Propter Hoc
(False Cause)
• “After this, therefore because of this”
• Assuming that because two things
happened, the first caused the second
one to happen.
Example:
Every time my Miss MacLachlan listens to
Lil Jon she is very angry.

12. Slippery Slope
• Implying that one small step in the wrong
direction will cause disastrous results
Example: If we allow Lil Jon to continue to
produce music, the whole hip-hop industry
will be destroyed.

14. Appeal to authority
• Implying that because an authority
(someone/something in a position of
power) thinks something is true, it must
therefore be true.
• Miss MacLachlan thinks that Lil Jon is the
worst rapper alive, she is a teacher, so it
must be true.

15. The other logical fallacies
While I do not expect you to learn every
single fallacy inside out. I do expect you to
at least glance through the following.

16. Begging the Question
• The opinion to be proved is given as if it
were already proved.
Example:
Aliens exist because I was abducted by
aliens.

17. Evasion
• Ignoring or evading the questions
• Example:
Miss MacLachlan: “Where is your
homework?
Philosophy pupil: “Miss have you heard the
new Taylor Swift album.”

18. Oversimplification
• Making a complicated issue seem very
simple by using simple terms or
suppressing information
Example: The polar icecaps are melting as
we do not turn off the lights when we leave
a room.

19. Red Herring
• Presenting an argument unrelated to your
subject in order to distract the reader
• Example: In order to really look at the
problem of polar ice caps melting, we
must first consider why Lil Jon is allowed
to still make music.

20. Two wrongs make a right
• Defending something done wrong by citing
another incident of wrong doing
Example: Lil Jon does not need stop
making music because Justin Bieber is
still producing much worse music.

21. Hasty Generalization
• An inference drawn from insufficient
evidence.
• Miss MacLachlan cannot find her keys;
therefore, aliens.