Logical Fallacies
A logical fallacy is “a failure in reasoning which renders an argument invalid.” Don’t commit logical fallacies!! If your opponents commit a logical fallacy, heckle the name of the logical fallacy when they make the mistake. Then, your team’s next speech, explain 1) what the logical fallacy is, 2) why what the other team said was a logical fallacy. Below are the most common types of logical fallacy in addition to an example for each.
Correlation not Causation/False Cause
Arguing that, because two things happened together or one happened before the other, one must be causing the other.
For example: “During the 1990s, police budget increased while crime rates dropped; therefore, higher police budgets reduce crime.”
False Dichotomy
Stating that there are only two options, thereby ignoring all alternatives.
For example: “When it comes to the question of whether the United States should intervene militarily in Ukraine to repel the Russian invasion, it is either military intervention or appeasement—military intervention or doing nothing while people suffer.”
Slippery Slope
Arguing that one thing will lead to another, which will lead to another, etc., leading to a very good or very bad outcome that is clearly unlikely.
For example: “If the United States makes it easier to prosecute police officers for their actions, police officers will be more hesitant to enforce the law; if police are more hesitant to enforce the law, crime rates will increase; if crime rates increase, the American economy will suffer; if the American economy suffers, there will be a global economic collapse; if there is a global economic collapse, countries will resort to nuclear warfare.”
Straw Man
Attacking a mischaracterized version of your opponents’ arguments instead of their actual argument.
For example: “The proposition team stated that we should create a government monopoly in the realm of healthcare, a policy that would stifle innovation and asphyxiate the American medical industry” (When the proposition really advocated for a public option for healthcare)
Anecdotal
Using one example to claim that a general statement is true or false.
For example: “Steve Jobs did not complete college yet was very successful; therefore, a college education is not conducive to success, and the government should not increase funding to upper education.”
Middle Ground
Arguing that something is good just because it is the “moderate” option.
For example: “Imposing sanctions on Iran is necessarily the optimal decision because we advocate for neither of the two extreme measures: appeasement or military invasion.”
Bandwagon/Appeal to Populace/Ad Populum
Arguing that something is good just because the majority supports it.
For example: “63% of US adults support a single payer healthcare system; therefore, the US should adopt such a system.”
Appeal to Authority
Arguing that something is good just because some authority figure says so.
“According to Elon Musk, artificial intelligence (AI) has the potential to wipe out humanity in a Terminator-like apocalypse; therefore, the US government should not fund research into AI.”
Appeal to Emotion
Making an argument purely based on emotion and without any logic to it.
For example: “There are poor, starving children in Madagascar; therefore, you should eat your vegetables.”
Appeal to Nature
Arguing that something is good just because it is “natural.”
For example: “Genetically modified foods are intrinsically unnatural, meaning that they are unhealthy and should be restricted.”