post hoc ergo propter hoc:
• The fact that one event or action follows another in time is necessary but not sufficient to establish that the first caused the second.
à Can pose a problem in research – how do you prove cause?
- One event occurring before another is necessary, but not sufficient
tu quoque (appeal to hypocrisy)
- Establishing that somebody is a hypocrite does not establish that his/her factual claim is false
- Proving that these kids’ parents smoke does not disprove the claim that smoking is harmful. It is irrelevant to the factual validity of the claim
whataboutism (a form of appeal to hypocrisy)
• Hypocrisy is wrong and often unjust HOWEVER…
• Establishing hypocrisy is NOT enough to invalidate the claim
– similar to ad hominem. Irrelevant who makes the argument
• “Child labour is harmful to children in the developing world.”
– “But the developed world used child labour to develop…”
Ø Two wrongs don’t make a right
à Irrelevant to the claim that child labour is harmful
“both sides do it fallacy”
- Is it TRUE that both sides do it?
- if YES - APPEAL to HYPOCRISY or COMMON PRACTICE
Both sides doing it does NOT prove the behavior is legal or moral or good
- if YES - APPEAL to HYPOCRISY or COMMON PRACTICE
- if NOT – Fallacy of False Equivalence
The existence of two sides does NOT make them equivalent
ad hominem (lit.: “attack on the man”)
• Literally “attack on the man”
• Attacks on the characteristics of the speaker which do not disprove the claim being made
A staple of talk shows and politics
• Even if the attack is accurate, this is still a fallacious type of argument
à Even if the Unabomber thinks climate change is real, that is irrelevant to the merits of the argument
à What matters is the merits, the validity of the claim, not who said it
ad hominem circumstantial (appeal to motive
• Establishing that the person making the claim has self-interest in making that claim does not refute their claim
• You can’t rebut climate scientists by noting that they make their living by it
• But can’t refute oil companies’ climate denial that way either
Focus on content, not who said it
genetic fallacy:
• “Modern highway systems were first developed and promoted by Fascists, such as Mussolini and Hitler. Therefore, highways are bad.”
Ø Establishing the historical origins of a practice or idea does not establish the truth of the claim.
middle ground fallacy (appeal to moderation):
• The truth in two opposing views is to split the difference and take the middle position
à WRONG. Being the middle position does not make it true.
à Being the middle position does not establish the validity of the claim
- validity is established by merits of the argument
• Making a policy recommendation that splits the difference may result in incoherent, even disastrous, policy
slippery slope:
• A single change will inevitably lead to an unstoppable cascade of consequences to an undesirable outcome
– Assumes one change triggers an unstoppable process
• Can’t be stopped or reversed
– Assumes that process unavoidably leads to a very bad outcome
No True Scotsman
Some people don’t even consider or avoid counter evidence - such as the no true scotsman fallacy: Protecting universal generalizations from a falsfying counter example by excluding the counter example You say no scotsman puts sugar in his porridge, when someone actually does, you reply but no true scotsman does Similiar to no true Christian supports legalized abortin, no true follower of the Qur’an supports suicide bombings.
Ø The fallacy creates an empirically unfalsifiable claim – if, when provided evidence to the contrary of the claim, the argument becomes that X is a not TRUE/REAL (Scotsman/American/Catholic/ Muslim/Man etc…)
Ø In argument, we need to use empirically observable, consistent categories in description (e.g. census categories, membership in institutions), not categories based on compliance with religious texts or normative principles or invoking God’s judgement (i.e. Who is a Christian? Catholic? Muslim?)
sunk cost fallacy:
- “I’ve already lost a lot money on this stock, so I need to hang onto it until it rebounds, to recoup my losses.”
- “If we don’t commit more troops to this battle, the lives of those who died will have been in vain.”
- In making decisions, we must decide based on future prospects for SUCCESS, not size of losses already incurred.
- The best possible outcome may be to CUT YOUR LOSSES NOW by selling/withdrawing/dumping
Bandwagon (appeal to common practice):
Popular, even majority, belief does not establish the truth of a claim
Argument ad baculam (Appeal to the threat of force):
à The threat of violence may be persuasive but it doesn’t establish the validity of the argument. It does not offer a relevant reason for supporting the troops.
False analogy/false equivalence:
Appeal to reasoning by analogy, when there are significant differences between the cases
Ø Not every foreign policy case is analogous to Chamberlain appeasing Hitler in Munich in 1938
Appeal to ignorance:
• Also known as “shifting the burden of proof”
à Wrongly implies that a lack of knowledge supports a particular claim
à Because barring entry of a particular group of people to the US would be an extraordinary course of action, there is an extra burden of proof. The burden of proof lay with Trump to provide valid, factual reasons in support of his proposal.
False dichotomy (or false dilemma):
• The merits of accepting refugees are independent of the merits of assistance to military veterans
• Agreeing that vets deserve assistance does not establish that refugees don’t
• There is no logical reason why it would be impossible to do both
Ø Hence it presents a false dilemma
Perfectionist fallacy:
• “Gun control laws won’t stop all mass shootings, therefore there should be no legal restrictions on guns.”
Anything less than 100% solution is unacceptable
This does not make a case why any improvement less than 100% is not worth pursuing
Appeal to emotion: argumentam ad metam
• The ad does not offer a reason why a vote against Johnson is a vote for nuclear annihilation
Also 2. False dichotomy
- There are many options for human interaction in addition to love and murder.
Special pleading:
Making a weak argument for an exception from a rule, law or principle (“My cause is special! I’m special!”)
• Example here is a ban on campfires, with no exemptions or exceptions
• It is special pleading when people’s response to the campfire ban is
– “Yes, but…” OR
– “We were just…”
