This review from the 3rd edn (A Rulebook for Arguments
When we hear that two friends have had an argument, we think of them falling out, of having "a verbal fistfight" and possibly even a real one, and of this being not at all a good thing (although our ears still prick up). In his introduction to this excellent little book, Anthony Weston provides a more positive account: "to give an argument" means "to offer a set of reasons or evidence in support of a conclusion". This kind of argument is neither simply a statement of certain views nor a dispute, but an attempt to support those views with reasons. "Not all views are equal. Some conclusions can be supported by good reasons; others have much weaker support." Argument is essential "because it is a way of trying to find out which views are better than others".
As the title implies, Weston's approach is not intended to be definitive. Brevity is one of the book's virtues, and he takes seriously his own rule 4: "Be concrete and concise". Good reasoning is so important, mastery of the basics so elusive, that focusing on a few fundamentals is a worthwhile strategy. The trouble is, most of us imagine we are well-enough equipped already, so why bother with a book like this? That it's always the other person who is not being reasonable should give us pause: could we ever be that "other person"? Given how often even these few rules are broken in everyday life, and given how easy it is to remain unaware of their transgression, the answer is of course yes. Equally obviously, those most in need of a dose of logical thinking will be among the least likely to pick up a book like this.
"Start from reliable premises', "Avoid loaded language", "Stick to one meaning for each term" hardly seem worth spelling out, and yet how many of us have never tried to rest a conclusion on a weak premise, or used emotive words, or been guilty of equivocation? After these general rules, Weston goes on to discuss several common types of argument - by example, by analogy, from authority, about causes - before ending with chapters on deductive arguments, composing an argumentative essay and fallacies.
Arguments by example are often more anecdote than argument. Beware of the "person who" formula - "I know a person who smoked fifty a day and lived to be a hundred" - and always check: Are the examples representative or biased? Have counterexamples been considered? Is too much weight being placed on a single vivid example?
For arguments by analogy, check for relevant similarities. Just as we can infer the existence of an architect or carpenter when we see a beautiful and well-built house, one such argument goes, so can we infer the existence of a creator from the order and beauty of the world. But the universe is not relevantly similar to a house. "The world is different from a house in at least this: A house is part of a larger whole, the world, while the world itself (the universe) is the largest of wholes." Weston concludes that this analogy "makes a poor argument" that does not establish the existence of a creator.
In discussing this particular argument Weston refers to David Hume, someone who might be considered an authority. In so doing he sets a good example of how we should treat any authority. He doesn't just appeal to this philosopher's preeminence, saying that because Hume said so it must be true, and he doesn't just make a vague reference. He makes sure he understands what Hume is claiming, he quotes Hume's words and cites the source, so we can look it up if we like. Most important, he does not assume that Hume is infallible. Relying on others can be a risky business. "Everyone has their biases. Supposed authorities may mislead us, or may be misled themselves, or may miss key parts of the big picture." Or they may claim to know what they could not possibly know: "religious moralists often have declared that certain practices are wrong because they are contrary to the will of God". It is one thing to believe there is such a thing as God's will, another to separate its contents from each and every personal prejudice and cognitive bias.
Arguments about causes crop up regularly in our personal and professional lives, and in public policy at all levels. The human mind is very good at detecting causal patterns in the world, so good in fact that it often sees a cause where there is only coincidence: "mere correlation, by itself, does not establish a cause-and-effect relationship" and neither does it establish the direction of causality. And where a causal relationship does exist, the causes may be complex and irreducible to a snappy headline.
Unusually for a highly recommended and rewarding book, I can almost guarantee this will also cause a good deal of intellectual pain, such are the irrationalist tendencies of our time. You won't have to wait very long to come across someone breaking one or more of these rules. When that happens, we still have an argument, only it is a misleading argument, a fallacy. The final chapter covers a few classical fallacies, including perhaps the two most common temptations: drawing conclusions from too little evidence, and overlooking alternatives.
Rulebooks are not supposed to be the most readable of works, but Anthony Weston's easygoing style and judicious use of examples make the logical medicine slip down. He keeps the jargon to a minimum, and shows us what happens when rhetoric wins out over reason. He reminds us that it is not a mistake to have strong views. "The mistake is to have nothing else." Above all, a good argument "offers reasons and evidence so that other people can make up their minds for themselves". Argument is essential if you value inquiry over revelation and if you value truth over deception.