Understanding Toulmin Logic

The Claim

The claim is the thesis or the central argument of the Toulmin essay.

Grounds

Evidence, reasons, and support comprise the grounds of the Toulmin essay.

Warrants

Warrants answer this question: Exactly how do the reasons offered in support of the conclusion work together?

In other words, what kind of guarantee—or warrant—is provided to demonstrate that the reasons proffered actually do support the claim or lead to the conclusion?

Perhaps the most simple way to explain this is to say that the warrants are the logic used to connect the grounds to the claim.

Example:

Claim: We need harsher fines and possible jail time for texting while driving.

Grounds: In spite of current texting-while-driving laws, the offense is on the rise. In fact, it’s up 50% from last year.

Warrant: Making people dig deeper into their pockets and scaring them with the possibility with heavy jail time will be a more effective deterrent than the current penalties.

Backing

Backing is using further logic to convince reader that you have chosen compelling and appropriate reasons for supporting your claim.

Modal Qualifiers

Modal qualifiers define the character and scope of the proposition or claim.

Unless there is evidence that the current laws are discouraging texting while driving . . .

In most cases, drivers who know that the penalties for texting while driving can be up to $3,000 and 2 years of jail time . . .

Rebuttals

At this point in your essay, you ask what are the possible objections to my argument? And what are the most compelling objections?

Can I state these counterarguments and rebuttal them effectively?

The Locavore Myth

Buy local, shrink the distance food travels, save the planet. The locavore movement has captured a lot of fans. To their credit, they are highlighting the problems with industrialized food. But a lot of them are making a big mistake. By focusing on transportation, they overlook other energy-hogging factors in food production.

Take lamb. A 2006 academic study (funded by the New Zealand government) discovered that it made more environmental sense for a Londoner to buy lamb shipped from New Zealand than to buy lamb raised in the U.K. This finding is counterintuitive–if you’re only counting food miles. But New Zealand lamb is raised on pastures with a small carbon footprint, whereas most English lamb is produced under intensive factory-like conditions with a big carbon footprint. This disparity overwhelms domestic lamb’s advantage in transportation energy.

New Zealand lamb is not exceptional. Take a close look at water usage, fertilizer types, processing methods and packaging techniques and you discover that factors other than shipping far outweigh the energy it takes to transport food. One analysis, by Rich Pirog of the Leopold Center for Sustainable Agriculture, showed that transportation accounts for only 11% of food’s carbon footprint. A fourth of the energy required to produce food is expended in the consumer’s kitchen. Still more energy is consumed per meal in a restaurant, since restaurants throw away most of their leftovers.

Locavores argue that buying local food supports an area’s farmers and, in turn, strengthens the community. Fair enough. Left unacknowledged, however, is the fact that it also hurts farmers in other parts of the world. The U.K. buys most of its green beans from Kenya. While it’s true that the beans almost always arrive in airplanes–the form of transportation that consumes the most energy–it’s also true that a campaign to shame English consumers with small airplane stickers affixed to flown-in produce threatens the livelihood of 1.5 million sub-Saharan farmers.

Another chink in the locavores’ armor involves the way food miles are calculated. To choose a locally grown apple over an apple trucked in from across the country might seem easy. But this decision ignores economies of scale. To take an extreme example, a shipper sending a truck with 2,000 apples over 2,000 miles would consume the same amount of fuel per apple as a local farmer who takes a pickup 50 miles to sell 50 apples at his stall at the green market. The critical measure here is not food miles but apples per gallon.

The one big problem with thinking beyond food miles is that it’s hard to get the information you need. Ethically concerned consumers know very little about processing practices, water availability, packaging waste and fertilizer application. This is an opportunity for watchdog groups. They should make life-cycle carbon counts available to shoppers.

Until our food system becomes more transparent, there is one thing you can do to shrink the carbon footprint of your dinner: Take the meat off your plate. No matter how you slice it, it takes more energy to bring meat, as opposed to plants, to the table. It takes 6 pounds of grain to make a pound of chicken and 10 to 16 pounds to make a pound of beef. That difference translates into big differences in inputs. It requires 2,400 liters of water to make a burger and only 13 liters to grow a tomato. A majority of the water in the American West goes toward the production of pigs, chickens and cattle.

The average American eats 273 pounds of meat a year. Give up red meat once a week and you’ll save as much energy as if the only food miles in your diet were the distance to the nearest truck farmer.

If you want to make a statement, ride your bike to the farmer’s market. If you want to reduce greenhouse gases, become a vegetarian.

James E. McWilliams, the author of Just Food, is an associate professor of history at Texas State University.

Recognizing Logical Fallacies

Begging the Question

Begging the question assumes that a statement is self-evident when it actually requires proof.

Major Premise: Fulfilling all my major desires is the only way I can be happy.

Minor Premise: I can’t afford when of my greatest desires in life, a Lexus GS350.

Conclusion: Therefore, I can never be happy.

Circular Reasoning

Circular reasoning occurs when we support a statement by restating it in different terms.

Stealing is wrong because it is illegal.

Admitting women into the men’s club is wrong because it’s an invalid policy.

Your essay is woeful because of its egregious construction.

Your boyfriend is hideous because of his heinous characteristics.

I have to sell my car because I’m ready to sell it.

I can’t spend time with my kids because it’s too time consuming.

I need to spend more money on my presents than my family’s presents because I need bigger and better presents.

I’m a great father because I’m the best father my children have ever had.

Weak Analogy or Faulty Comparison

Analogies are never perfect but they can be powerful. The question is do they have a degree of validity to make them worth the effort.

A toxic relationship is like a cancer that gets worse and worse (fine).

Sugar is high-octane fuel to use before your workout (weak because there is nothing high-octane about a substance that causes you to crash and converts into fat and creates other problems)

Free education is a great flame and the masses are moths flying into the flames of destruction. (horribly false analogy)

Ad Hominem Fallacy (Personal Attack)

“Who are you to be a marriage counselor? You’ve been divorced six times?”

A lot of people give great advice and present sound arguments even if they don’t apply their principles to their lives, so we should focus on the argument, not personal attack.

“So you believe in universal health care, do you? I suppose you’re a communist and you hate America as well.”

Making someone you disagree with an American-hating communist is invalid and doesn’t address the actual argument.

“What do you mean you don’t believe in marriage? What are you, a crazed nihilist, an unrepentant anarchist, an immoral misanthrope, a craven miscreant?”

Straw Man Fallacy

You twist and misconstrue your opponent’s argument to make it look weaker than it is when you refute it. Instead of attacking the real issue, you aim for a weaker issue based on your deliberate misinterpretation of your opponent’s argument.

“Those who are against universal health care are heartless. They obviously don’t care if innocent children die.”

Hasty Generalization (Jumping to a Conclusion)

“I’ve had three English instructors who are middle-aged bald men. Therefore, all English instructors are middle-aged bald men.”

“I’ve met three Americans with false British accents and they were all annoying. Therefore, all Americans, such as Madonna, who contrive British accents are annoying.” Perhaps some Americans do so ironically and as a result are more funny than annoying.

Either/Or Fallacy

There are only two choices to an issue is an over simplification and an either/or fallacy.

“Either you be my girlfriend or you don’t like real men.”

“Either you be my boyfriend or you’re not a real American.”

“Either you play football for me or you’re not a real man.”

“Either you’re for us or against us.” (The enemy of our enemy is our friend is every day foreign policy.)

“Either you agree with me about increasing the minimum wage, or you’re okay with letting children starve to death.”

“Either you get a 4.0 and get admitted into USC, or you’re only half a man.”

Equivocation

Equivocation occurs when you deliberately twist the meaning of something in order to justify your position.

“You told me the used car you just sold me was in ‘good working condition.’”

“I said ‘good,’ not perfect.”

The seller is equivocating.

“I told you to be in bed by ten.”

“I thought you meant be home by ten.”

“You told me you were going to pay me the money you owe me on Friday.”

“I didn’t know you meant the whole sum.”

“You told me you were going to take me out on my birthday.”

“Technically speaking, the picnic I made for us in the backyard was a form of ‘going out.’”

Red Herring Fallacy

This fallacy is to throw a distraction in your opponent’s face because you know a distraction may help you win the argument.

“Barack Obama wants us to support him but his father was a Muslim. How can we trust the President on the war against terrorism when he has terrorist ties?”

“You said you were going to pay me my thousand dollars today. Where is it?”

“Dear friend, I’ve been diagnosed with a very serious medical condition. Can we talk about our money issue some other time?”

Slippery Slope Fallacy

We go down a rabbit hole of exaggerated consequences to make our point sound convincing.

“If we allow gay marriage, we’ll have to allow people to marry gorillas.”

“If we allow gay marriage, my marriage to my wife will be disrespected and dishonored.”

Appeal to Authority

Using a celebrity to promote an energy drink doesn’t make this drink effective in increasing performance.

Listening to an actor play a doctor on TV doesn’t make the pharmaceutical he’s promoting safe or effective.

Tradition Fallacy

“We’ve never allowed women into our country club. Why should we start now?”

“Women have always served men. That’s the way it’s been and that’s the way it always should be.”

Misuse of Statistics

Using stats to show causality when it’s a condition of correlation or omitting other facts.

“Ninety-nine percent of people who take this remedy see their cold go away in ten days.” (Colds go away on their own).

“Violent crime from home intruders goes down twenty percent in home equipped with guns.” (more people in those homes die of accidental shootings or suicides)

Post Hoc, Confusing Causality with Correlation

Taking cold medicine makes your cold go away. Really?

The rooster crows and makes the sun go up. Really?

You drink on a Thursday night and on Friday morning you get an A on your calculus exam. Really?

You stop drinking milk and you feel stronger. Really? (or is it placebo effect?)

Non Sequitur (It Does Not Follow)

The conclusion in an argument is not relevant to the premises.

Megan drives a BMW, so she must be rich.

McMahon understands the difference between a phrase and a dependent clause; therefore, he must be a genius.

Whenever I eat chocolate cake, I feel good. Therefore, chocolate cake must be good for me.

Bandwagon Fallacy

Because everyone believes something, it must be right.