Brains & Bread Trails: The Rhetorical Appeal to Logic
Understanding appeals to logic can be difficult, mostly because most people experience the word "logic" as a powerful sedative. An effective argument, a presentation of ideas or opinions, should include a solid logical structure. Recognizing logic and logical fallacies is easy once you know the basics.
An appeal to logic begins with a statement or premise. A statement should be supported by proofs. Meaning, if one makes a claim, they should provide credible proofs to support it.
Proofs can be sorted into two categories: intrinsic and extrinsic. Intrinsic proofs come directly from the speaker or writer and take the form of examples, analogies, and analysis. Extrinsic proofs come from outside the speaker or writer, and often take the form of common knowledge, data or information the speaker can cite or reference.
Effective arguments should include a balance of intrinsic and extrinsic proofs, particularly those arguments that ask readers or listeners to take a future action such as voting in a election, determining policy, serving on a jury, weighing competing ideas, or responding to a common problem in need of address.
The two most common logic structures, or orders of reasoning, are deductive and inductive. Deductive reasoning begins with a claim and is followed by proofs. Inductive reasoning begins with the proofs and ends with the claim positioned as a "therefore" statement.
Logical appeals and reasoning help us to make decisions about important issues, determine when we are being manipulated, and to weigh the merits of an idea, action, or ideology. By thinking through the logic of an idea or proposed action, one is able to move beyond the appetites of ego and emotion, the comforts of ignorance and inaction, and do the hard work of shared governance in a complex democracy. Understanding logical appeals can also help us to make better decisions at our jobs, within our relationships with those we love, and within our communities.
The rhetorical rule of thumb is that one must support a statement or claim with proof. Of course, there are many people who fail to follow such a fundamental rule. Too often, those on cable news channels make claims without providing adequate logical proofs. Often, statements are supported with appeals to emotion rather than logic. Too often, statements are supported by additional statements that restate the original claim.
When a speaker or writer does this, they are working with logical fallacies. There's a fine line between entertainment and propaganda these days, and those toeing it seem to be pandering to emotions rather than logic. No matter which channel you choose, you'll find this phenomenon once you recognize the basic patterns of logic.
In my next blog post, I will explore the most common logical fallacies used in public discourses today.
Tips for Identifying Appeals to Logic
1. Listen for the statement or claim, the "premise."
2. Listen for the proofs that support that statement.
3. Determine if the proofs are intrinsic or extrinsic.
4. Make sure extrinsic proofs come from credible and citable
sources.
5. Repeat as needed.