Logical Fallacies
by J.D. AdamsJuly 8th, 2007 at 15:49:08
In debate, it is not uncommon for arguments to break down due to weakness in the reasoning process. These false arguments may be due to ignorance or may be intentional. Indeed, the Latin word fallere, from which fallacy is taken, means to deceive. Intelligent readers learn to recognize these arguments, and conscientious writers should avoid them.
To assist in accurate debate here and elsewhere, I’m referencing a list of common logical fallacies from one of my college textbooks. You may deduce that many arguments rely on illogical deductions and false premises to persuade the reader.
1. Guilt by Association
Just because two things may share an attribute doesn’t mean they are the same.
2. Hasty Generalizations
This fallacy involves drawing conclusions on the basis of insufficient evidence. Many prejudices and superstitions are the result of judgments made before the facts are in.
3. Faulty Use of Authority
Is an attempt to bolster claims by citing the opinions of experts who may disagree. In this case, carefully evaluate the credentials of authorities, seek consensus, and be aware that interpretations are less reliable then other kinds of support.
4. Post Hoc or Doubtful Cause
The entire Latin term means “After this, therefore because of this.” The argument infers that because one event follows another event, the first is the cause of the second, when in fact no such relationship exists.
5. False Analogy
Analogies that are descriptive or superficial, while offering no proof of a connection between two things being compared, fall under this category.
6. Ad Hominem
Latin for “against the man”. A diversionary tactic, this fallacy refers to attacks on the person rather than the issue under discussion. The assumption is that if the speaker is unacceptable in some way, then his or her argument must also be judged unacceptable.
7. False Dilemma
This represents the oversimplification of a complex problem. The arguer proposes that only two alternatives exist, when there may be other explanations or solutions to a particular situation. Also known as the black-white fallacy.
8. Slippery Slope
Hinges on distinguishing between probable and improbable predictions. An arguer who predicts that a first step will inevitably lead to a second, undesirable step, without providing evidence, is guilty of the slippery slope fallacy.
9. Begging the Question
In this fallacy, a writer falsely assumes that the very question being debated has already been proven. Circular arguments also fall under this category.
10. Straw Man Fallacy
Another diversionary tactic that consists of an attack on a viewpoint close to, but not identical to the one your opponent holds.
11. Two Wrongs Make a Right
Yet another diversion consisting of responding to allegations of wrongdoing with counter-allegations.
12. Non Sequitar
A Latin term meaning “it does not follow”, involving an irrelevant connection between two things, like the popularity of a book versus the theoretical soundness of the text.
13. Ad Populum
Latin for “the people”. Those guilty of this popular fallacy appeal to common prejudices, assuming that their claim can be defended by emphasizing a shared belief or attitude.
14. Appeals to Tradition
The arguer assumes that what has been in the past should continue solely because of tradition, without explaining why it should be preserved.
15. Faulty Emotional Appeals
Not all emotional appeals are invalid; they can be appropriate and persuasive. But fallacious appeals are irrelevant or distractive to the argument, or they might conceal another purpose.
A good reference is “Elements of Argument” by Annette T. Rottenberg. For your homework, I’d like you to examine some of the arguments posed by antibiofuelmania and determine which of the many fallacies above are being used.
Hint: almost all of them.
July 10th, 2007 at 5:02 pm
Here is some rebuttal to typical antibiofuel arguments -
Algaculture, from Wikipedia,
From 1978 to 1996, the U.S. National Renewable Energy Laboratory experimented with using algae as a biodiesel source in the “Aquatic Species Program”. [32] A recent paper from Michael Briggs, at the UNH Biodiesel Group, offers estimates for the realistic replacement of all vehicular fuel with biodiesel by utilizing algae that have a natural oil content greater than 50%, which Briggs suggests can be grown on algae ponds at wastewater treatment plants.[26] This oil-rich algae can then be extracted from the system and processed into biodiesel, with the dried remainder further reprocessed to create ethanol.
The production of algae to harvest oil for biodiesel has not yet been undertaken on a commercial scale, but feasibility studies have been conducted to arrive at the above yield estimate. In addition to its projected high yield, algaculture — unlike crop-based biofuels — does not entail a decrease in food production, since it requires neither farmland nor fresh water. Some companies[9][10] are pursuing algae bio-reactors for various purposes, including biodiesel production.
On May 11, 2006 the Aquaflow Bionomic Corporation in Marlborough, New Zealand announced that it had produced its first sample of bio-diesel fuel made from algae found in sewage ponds. [17] Unlike previous attempts, the algae was naturally grown in pond discharge from the Marlborough District Council’s sewage treatment works.
and:
http://engineering.suite101.com/blog.cfm/increasing_biofuel_efficiency
Much of this is exacerbated by the general loss of farmland to development, a process that’s been going on since before the 50’s.