Fallacious Logos

  • Appeal to Nature: Suggesting a certain behavior or action is normal/right because it is “natural.” This is a fallacious argument for two reasons: first, there are multiple, and often competing, ways to define “nature” and “natural.” Because there is no one way to define these terms, a writer cannot assume his or her reader thinks of “nature” in the same way he or she does. Second, we cannot assume that “unnatural” is the same as wrong or evil. We (humans) have made lots of amendments to how we live (e.g., wearing clothes, living indoors, farming) with great benefit.
  • Argument from Ignorance: Assuming something is true because it has not been proven false. In a court of law, a defendant is, by law, “innocent until proven guilty.” However, judges and jurors must hear testimonies from both sides and receive all facts in order to draw conclusions about the defendant’s guilt or innocence. It would be an argument from ignorance for a judge or juror to reach a verdict without hearing all of the necessary information.
  • Straw Man: Intentionally misrepresenting your opponent’s position by over-exaggerating or offering a caricature of his or her argument. It would be fallacious to claim to dispute an opponent’s argument by creating a superficially similar position and refuting that position (the “straw man”) instead of the actual argument. For example, “Feminists want to turn men into slaves.” This statement fails to accurately represent feminist motivations—which can be very diverse. Most feminists agree in their goal to ensure women’s equality with men. Conceptions of equality can vary among feminists, but characterizing them as men-haters detracts from their true motivations.


  • False Dilemma: Assuming that there are only two options when there are, in fact, more. For example, “We either cut Social Security, or we have a huge deficit.” There are many ways to resolve deficit problems, but this statement suggests there is only one.
  • Hasty Generalization: Drawing a broad conclusion based on a small minority. For instance, if you witnessed a car accident between two women drivers, it would be a hasty generalization to conclude that all women are bad drivers.

  • Cum Hoc, Ergo Propter Hoc (With This, Therefore Because of This): Confusing correlation with causation—that is, thinking that because two things happened simultaneously, then one must have caused the other. For example, “There has been an increase in both immigration and unemployment; therefore, immigrants are taking away American jobs.” This statement is fallacious because there is no evidence to suggest that immigration and unemployment are related to each other—other than that their rates increased simultaneously.

  • The Slippery Slope: We already noted that the slippery slope argument is often a way to scare readers or listeners into taking (or not taking) a particular action (see “Fallacious Pathos“). The slippery slope argument can also function as a false invocation of logic or reason in that it involves a causal statement that lacks evidence. For example, I might argue that if the drinking age were lowered from 21 to 18, vast numbers of college students would start drinking, which in turn would lead to alcohol poisoning, binge drinking, and even death. This conclusion requires evidence to connect the legality of drinking with overindulgence. In other words, it does not follow that college students would drink irresponsibly if given the opportunity to drink legally.