Toulmin Logic & Logical Fallacies Toulmin Method of Argument Claim: The overall thesis the writer will argue for. Data: Evidence gathered to support the claim. Warrant (also referred to as a bridge): Explanation of why or how the data supports the claim, the underlying assumption that connects your data to your claim. Backing (also referred to as the foundation): Additional logic or reasoning that may be necessary to support the warrant. Counterclaim: A claim that negates or disagrees with the thesis/claim. Rebuttal: Evidence that negates or disagrees with the counterclaim. Toulmin cont’d Data Definition: the evidence which you cite to support your claim. Like a lawyer presenting evidence to a jury, you must support your claim with facts; an unsupported claim is merely an assertion. Data can include: Facts or statistics: objectively determined data about your topic. (Note: just what constitutes "objective" may be open to debate.) Expert opinion: the media and our essays are full of learned opinions which you should cite frequently, both to support your argument and to disagree with. Authors must be quoted and properly cited in your paper. Personal anecdotes: the most difficult kind of data to use well, for doing so requires a persuasive argument that your own experience is objectively grasped and generalizable. Personal experience can, however, help bring an argument to life. Toulmin cont’d Warrant definition: the warrant interprets the data and shows how it supports your claim. The warrant explains why the data proves the claim. In trials, lawyers may agree on data but hotly dispute warrants. A good warrant will… Be a reasonable interpretation of the facts Not make illogical interpretive leaps Not assume more than the evidence supports May consider and respond to possible counter-arguments Example Claim: Carol should be elected class president Data: Carol is an honors student Warrant: A person who is an honor student would make a good class president Fallacy Definition A fallacy is an error in thinking, logic, or argumentation. To create an effective argument, it is important to avoid fallacies. Appeal to authority – often people will attempt to strengthen an argument with references to famous people or experts. These appeals are not valid when the individual cited has no expertise on issue. EX) “Noted psychologist Dr. Anthony Bryant recommends that you buy the EZ-Rest Hot Tub.” Either/or dilemma (false dilemma)– suggestion that only two alternatives exist even though there may be others EX) “Either go to college or forget about making money." Begging the question (circular reasoning)– assumes a statement is true when it actually requires proof; using a premise to support itself EX) “The belief in God is universal. After all, everyone believes in God." Hasty generalization (jumping to a conclusion)– basing a conclusion on insufficient evidence EX) "Wow! Did you see that teenager run that red light? Teenage drivers are really pathetic.” Faulty comparison/analogy – comparing two unlike items to force a particular conclusion EX) “Employees are like nails. Just as nails must be hit in the head in order to make them work, so must employees.” Ad hominem (personal attack) – an attack on the character of the opponent instead of dealing with the actual argument EX) “She never graduated college so what does she know?” “Her husband cheated on her; do we really want her in the White House?” Post hoc reasoning (false cause)– assumes that because two events occur close together in time, the first must be the cause of the second EX) “Joan is scratched by a cat while visiting her friend. Two days later she comes down with a cold. Joan concludes that the cat's scratch must be the cause of her illness.” Red herring – diverting attention away from the actual issue EX) "I think there is great merit in making the requirements stricter for the graduate students. I recommend that you support it, too. After all, we are in a budget crisis and we do not want our salaries affected." Straw man – deliberating misstating an opponent’s position to make them easier to attack EX) “Teens should be taught about contraception.” Proponents of sex education want to give kids license to have sex with no consequences. (misstating the 1st statement) Slippery slope – assertion that some event must inevitably follow from another without any argument for the inevitability of the event in question EX) "We have to stop the tuition increase! The next thing you know, they'll be charging $40,000 a semester!"
