Building an argument that holds up

Here is an email you could have written last week. "We should move the team meeting to Monday morning. Fridays are dead anyway, half the team is already thinking about the weekend, and Monday sets the week up properly." It's not a bad email. Most people would nod and move on.

Now read it as someone who has done the first nine lessons of this course. There's an unstated premise (that a meeting works better when people are fresh) that nobody has checked. "Half the team" is a sample of one office on a couple of Fridays. "Sets the week up properly" is overtone doing the work of a reason. And the strongest objection, that Monday morning is when the people who actually run the week are busiest, isn't there at all. A careful reader will supply it, and a reader who has to supply your objections for you trusts the rest of your argument a little less.

That is the situation this lesson is about. For nine lessons you've been the reader with the checklist. Now you're the writer, and the checklist is coming for you. The good news is that you already own every tool you need. Building an argument that holds up is the six-step check run in reverse, on yourself, before anyone else gets the chance.

The core idea: write for the reader who will check you

Every tool in the course is a place where a reader can stop you. Lesson 1 taught them to find your missing premise. Lessons 2 to 4 taught them to test your link for validity and to build a counterexample if it fails. Lesson 5 taught them to ask how big your sample was and whether your analogy shares the feature that matters. Lesson 6 taught them to look for the base rate you left out. Lesson 7 taught them to notice when you've answered a version of the other side that nobody holds. Lesson 8 gave them names for the patterns and the critical questions that convict or acquit each one. Lesson 9 taught them to ask who your source is and how they know.

So the mechanism of a good written argument is simple to state. An argument survives when its best opponent has already been through it. If you run each of those checks on your own draft, you find the stops before your reader does, and you either fix them or say them out loud. What's left is an argument the reader can't stop, or can only stop at a place you've already marked.

Anthony Weston's A Rulebook for Arguments is the short book most often handed to students who need to write arguments rather than classify them, and its rules are the practical form of this idea.¹ The first six, for short arguments, are the ones you'll use most. Weston tells you to know what your premises and your conclusion are before you start; to unfold your ideas in a natural order (rule 2); to start from reliable premises (rule 3); to be concrete and concise (rule 4); to build on substance, not overtone (rule 5); and to use consistent terms (rule 6).¹

Read those against the Monday-meeting email. It fails rule 3 (the "half the team" premise isn't reliable), rule 5 ("sets the week up properly" is overtone), and it never states the premise the whole thing rests on. Three of six, in three sentences. That's typical of a first draft, including mine.

Worked example 1: a short argument, built rule by rule

Say you're deciding whether to buy a used car outright or lease a new one, and you want to write the case for buying so a friend can check it. This is a hypothetical case; the numbers are made up and the point is the method.

First draft, as most people would write it:

Buy the used car. Leasing is just renting, and you never own anything at the end. Everyone knows leasing is a rip-off.

Now run Weston's rules on it.

Rule 1, premises and conclusion. Conclusion: buy the used car. Premises: leasing is renting; you own nothing at the end; everyone knows leasing is a rip-off. Written out like that, the third premise isn't a reason, it's the conclusion in a different coat. Delete it.

Rule 3, reliable premises. "Leasing is renting" is roughly true but it's an analogy, and lesson 5 taught you that an analogy is only as good as the relevance of the shared feature. What feature is doing the work? Cost over the period you'll have the car. So replace the analogy with the thing it was standing in for.

Now here's the gap. Before you read on, write the premise that the argument actually needs about cost. Not "leasing costs more"; something a friend could check.

Rule 4, concrete and concise. "You never own anything at the end" becomes "at the end of a lease you hand the car back; at the end of five years of ownership you have a car worth about a fifth of what you paid." Rule 5, substance not overtone: "rip-off" goes. Rule 6, consistent terms: "cost" means total cost over five years everywhere, not monthly cost in one line and total in the next. That last one matters because the standard argument for leasing is "the monthly payment is lower", and it's true. Your argument has to meet it with the same word meaning the same thing.

Second draft, in the course's standard form:

1. Over the five years I expect to keep a car, buying this used car costs about £X in total, including purchase, repairs, and insurance, less about £Y I'd get back on resale.
2. Leasing a comparable new car for five years costs about £Z in total, including payments, fees, and end-of-term charges.
3. £X minus £Y is less than £Z.
4. [Other things being roughly equal, I should choose the option that costs less over the period I'll have the car.]

C: I should buy the used car.

The link is now deductive and valid: if 1 to 4 are true, the conclusion follows. Every premise is something a friend can check, and premise 4, the unstated one, is written down in brackets where the reader can see it. Look at what premise 4 does. It says "other things being roughly equal", and that's the door the objection walks through, which is the subject of the next section. A short argument that holds up doesn't hide that door. It marks it.

Worked example 2: when the objection is partly right

Short arguments are for decisions with two or three premises. Most real arguments are longer, and Weston's rules for extended arguments say what to do with the length: explore the issue (rule 29), spell out your basic ideas as arguments (rule 30), defend your basic premises with arguments of their own (rule 31), reckon with objections (rule 32), and explore alternatives (rule 33).¹ For an argumentative essay he adds: state your claim early and make it definite (rules 34 and 35), let the argument be the outline (rule 36), detail objections and meet them (rule 37), seek feedback and use it (rule 38), and, his last rule for essays, "Modesty, please!" (rule 39).¹

Rules 32 and 37 are where most first drafts die, and rule 39 is the one nobody expects. Here's an extended case where they all come into play. Again hypothetical.

You want to argue that you should learn Spanish this year. You explore the issue (rule 29): you have a work trip to Madrid in ten months, your partner's family speaks Spanish, and you've wanted to for years. You spell the basic ideas out as arguments (rule 30): the trip goes better with some Spanish; family conversations open up; a language is one of the few skills that reliably rewards steady practice. You defend the premises (rule 31): the trip is booked; the family is real; the practice claim has evidence behind it, which you'd cite. So far, a decent case.

Now rule 32. Reckon with the objection, and do it in Rapoport's form from lesson 7: state the other side so well that a holder of it would accept the statement.⁴ The best objection isn't "languages are hard". It's this: "You tried this two years ago with an app, did it daily for six weeks, then stopped when work got busy, and you never got past ordering food. Nothing about your time has changed. The problem was never motivation; it was that twenty minutes a day doesn't survive a busy month."

That objection is partly right. The history is accurate. The time hasn't changed.

Now draft the qualified conclusion yourself before you read mine. Use Toulmin's two slots from lesson 7: a qualifier ("presumably", "in most cases") and a rebuttal ("unless").⁵

Here's one version. "I should learn Spanish this year, presumably to a conversational level by the Madrid trip, unless I can't protect a fixed slot for it; so the actual claim is that I should book a weekly class with a teacher, which survives a busy month in a way that a solo app habit didn't, and review after eight weeks."

Notice what happened. The claim got narrower: not "learn Spanish" but "book a weekly class and review at eight weeks". It also got stronger, because the objection has been through it. The reader who was about to say "but you quit last time" finds that sentence already in the argument, answered by a mechanism (a booked class with a person expecting you is harder to drop than an app), and hedged exactly where it should be (unless the slot can't be protected, in which case the plan says what to do). The objection didn't beat the argument. It sharpened it.

This is what Weston means by "Modesty, please!" He says you'll very seldom put all the objections to rest, and that the world is an uncertain place, so summarise at the end fairly and don't claim more than you've shown.¹ Toulmin's qualifier is how you do that with precision rather than vagueness: "presumably" and "unless" say how far the argument reaches, which is information, whereas "it could perhaps be argued that" says nothing.⁵

Worked example 3: the conductive argument, with and without its other side

Lesson 5 introduced the conductive argument, named by Carl Wellman in 1971: several independent reasons for a conclusion, weighed against the considerations pulling the other way, with the weighing done in the open.³ Most practical arguments are this shape. Here's one, hypothetical, written out properly, and then written the way people usually write it.

The question: should a family replace their twelve-year-old car this year or run it one more year?

Version A, the conductive argument:

Reasons for replacing it now: the last two services cost more than a year of payments on a newer car; it failed its emissions test once and scraped through the second time; the youngest child starts school across town in September, so the daily mileage roughly doubles. Against: the car is paid off, and a newer one means a monthly payment for three years; replacing a car that still runs has an environmental cost that doesn't show up in the family's accounts; the service bills may have been a bad year rather than a trend. Weighing: the mileage change is the decisive reason, because it turns an occasional breakdown from an inconvenience into a missed school run twice a week, and the paid-off point is the strongest reason against, because it's money the family definitely has now against money they might save later. On balance, replace it this year, unless the September school run can be shared with another family, in which case wait.

Version B, the same argument with the counter-considerations silently dropped:

The last two services cost more than a year of payments on a newer car. It failed its emissions test once and barely passed the second time. And from September the daily mileage doubles. We should replace it this year.

Version B is shorter, cleaner, and more confident. Read it as the reader with the checklist. The first thing they'll do is supply what's missing: "It's paid off, though. And two expensive services might just be two expensive services." Now they're doing your weighing for you, and they'll do it less generously than you would have, because a writer who leaves out the other side either didn't think of it or hoped you wouldn't. Either way, the credit you'd have earned by stating it goes to the reader instead.

Version A is the more persuasive one to a careful reader, and it's the only one of the two that says what would change the verdict (the shared school run). That "unless" is the rebuttal slot again, and it's what makes the argument checkable rather than just assertive.

What people get wrong

"A strong argument has no weaknesses." It has stated ones. The argument for learning Spanish above has a weakness (the time problem), and the argument is stronger for saying so than it would be pretending otherwise. An argument with no stated weaknesses is an argument whose writer hasn't looked, and a reader with the checklist will look for them.

"Conceding is losing." Conceding the true part of an objection is what buys the rest of your argument its credibility. Weston's rule 32 exists because objections, in his words, tend to come as a shock to writers who have only thought about the pro side; the fix is to think about the other side first, on purpose.¹ Winning is when the other person stops talking. Being right is when the argument survives the check. This course teaches the second, and the two come apart more often than people expect: a debater who never concedes can win a room and be wrong about everything.

"More premises make a stronger argument." It depends on how they're joined, which lesson 7 covered. Convergent premises each support the conclusion on their own, so adding one adds a line of support. Linked premises only work together, so adding one adds another thing that has to be true, another place the argument can fail.³ The buy-the-car argument has four linked premises; every one of them has to hold. That's fine, because each one is checkable. It would not be fine to bolt on a fifth "and leasing is bad for the environment", because now the argument fails if that's false too, and it wasn't needed.

"Qualifiers are hedging." A qualifier is precision. Hedging is vagueness. "Presumably, unless X" tells the reader how far the claim reaches and what would defeat it. "It could be argued that, in some sense, perhaps" tells them nothing except that the writer is nervous. The style guide's rule for prose applies to arguments: say what's true, and where it's uncertain, say exactly how and why, once.

"Winning is the goal." If it were, the advice in this lesson would be backwards: never concede, hide the other side, use the warm words. Those tactics work on readers who aren't checking. They fail on readers who are, and they fail worst on the reader who matters most, which is you a year from now, trying to remember whether you believed this because it was true or because you argued it well.

Your self-check, in the order a reader will use it

Before you send anything, run the course on it. This is the six-step check turned round, and each line names the lesson that taught the reader to stop you there.

1. Is the conclusion stated, early, and definite? (Weston rules 34 and 35.)¹
2. Are the premises written out, including the ones you thought too obvious to say? Write the obvious one in brackets and look at it. (Lesson 1.)
3. What kind of link is it? If deductive, could the premises be true and the conclusion false? Build the counterexample yourself. If inductive, name the family (sample, analogy, cause, best explanation, conductive) and ask its question: how big and representative is the sample, does the analogy share the feature that matters, which of the four readings of the correlation have you ruled out. (Lessons 2 to 5.)
4. Is every premise acceptable to your reader, relevant to the conclusion, and enough, with the others, to carry it? That's the ARG test from lesson 7, run on yourself.⁶
5. Any number without its base rate or its denominator? Any "doubles the risk" without the absolute figure? (Lessons 6 and 9.)
6. Have you stated the strongest objection in a form its holders would sign, and either answered it or written the concession into the conclusion as a qualifier? (Lesson 7; Weston rules 32 and 37.)¹⁴
7. Does every important word mean one thing throughout? (Weston rule 6; equivocation, lesson 8.)¹
8. Any named pattern from lesson 8? Run its critical questions. A name isn't a verdict on your own argument any more than on anyone else's.
9. Who are your sources, how do they know, and who disagrees? (Lesson 9.)
10. Has anyone else read it? Weston's rule 38 is to seek feedback and use it, because what's clear to you may be far from clear to anyone else.¹

Here's the structure that comes out the other end, drawn as one picture so you can see where each piece sits.

The dashed line on the right is the one to remember. When you concede, the concession doesn't disappear into a paragraph near the end. It travels up and becomes part of the claim.

Practice: the project

This is the last practice section in the course, and it's the project. Everything below goes in the folder you started in lesson 1, and the project brief in the assessments folder tells you how it's marked.

Connections

This lesson is the whole course run backwards. Lesson 1's missing premise is the bracketed line in your own standard form. Lessons 2 to 5's tests for the link are what you name in step 3 of the self-check. Lesson 6's base rates are what you owe any number you use. Lesson 7's Toulmin layout gave you the qualifier and rebuttal slots, and its Rapoport rules gave you the objection paragraph; here they point at your own claim. Lesson 8's names are hypotheses to test on your own draft as much as on anyone else's. Lesson 9's questions for a source apply to the sources you cite.

Where it goes next: any Foval course in which you have to argue, which is most of them. History asks you to argue from evidence about what happened. Economics asks you to argue about what a policy does. Ethics and apologetics ask you to argue about what should be believed and done. The form is the same in each: a definite claim, premises a reader can check, a link you can name, the strongest objection stated fairly, and a conclusion that says exactly how far it reaches.

Go deeper

• Weston, A Rulebook for Arguments, 5th ed. (Hackett, 2018), chapters I, VII, and VIII: forty-odd pages that cover everything in this lesson with more examples; read it once now and keep it for when you're writing.
• Possin, K., "Conductive Arguments: Why is This Still a Thing?", Informal Logic 36(4), 2016 (open access): the conductive argument's history and the live dispute about whether it is a distinct kind at all, with Wellman quoted throughout.
• Dennett, Intuition Pumps and Other Tools for Thinking (2013), the short section on Rapoport's rules: two pages, and the clearest statement of why stating the other side well is not a courtesy but a method.
• Duke's Think Again series on Coursera (free to audit), especially the "How to Understand Arguments" course: the video companion to this whole course, and its exercises on constructing arguments are a good next step after the project.

Sources

1. Weston, A., A Rulebook for Arguments, 5th ed. (Hackett, February 2018, 118 pp). Rule numbers and titles verified against the publisher's edition in the Google Books preview at draft time: rule 2 "Unfold your ideas in a natural order" (p. 3), rule 3 "Start from reliable premises" (pp. 3 to 4, including the advice to do research or give an argument for a premise you are not sure of), rule 4 "Be concrete and concise" (pp. 4 to 5), rule 5 "Build on substance, not overtone" (pp. 5 to 6), rule 6 "Use consistent terms" (pp. 7 to 8); chapter VII Extended Arguments, rule 29 "Explore the issue" (p. 51), rule 30 "Spell out basic ideas as arguments" (p. 53), rule 31 "Defend basic premises with arguments of their own" (p. 55), rule 32 "Reckon with objections" (p. 57, with the observation that writers who attend only to the pro side find objections come as a shock), rule 33 "Explore alternatives" (p. 58); chapter VIII Argumentative Essays, rule 34 "Jump right in" (p. 61), rule 35 "Urge a definite claim or proposal" (p. 62), rule 36 "Your argument is your outline" (p. 63, which cross-references rule 6 on consistent terms), rule 37 "Detail objections and meet them" (p. 65), rule 38 "Seek feedback and use it" (p. 66, "what seems clear to you may be far from clear to anyone else"), rule 39 "Modesty, please!" (pp. 67 to 68: summarise fairly, don't claim more; you will very seldom put all the objections to rest, and the world is an uncertain place). Appendix I defines equivocation as sliding from one meaning of a term to another in the middle of an argument (p. 90). The wording of rule 1 was not visible in the preview and is paraphrased in the text without a rule number.
2. Magnus, P. D., Button, T., Trueman, R., Zach, R. et al., forall x: Calgary (Fall 2025, CC BY 4.0), chapter 2. To rebut an argument you can show a premise is not true or show the argument is not valid, and logic only helps with the latter. Read from the PDF for this course's SOURCES.md.
3. Possin, K., "Conductive Arguments: Why is This Still a Thing?", Informal Logic 36(4), 2016, 563 to 593 (open access), quoting Wellman, Challenge and Response: Justification in Ethics (1971), who named the conductive argument and described the verdict as coming from weighing the pros and the cons. Used for the shape and for Wellman's "negative considerations"; taught in full in lesson 5.
4. Dennett, D. C., Intuition Pumps and Other Tools for Thinking (Norton, 2013), "Rapoport's Rules": re-express the other position so well that its holder accepts the statement; list agreements; say what you learned; only then criticise. The four rules are paraphrased here, not quoted, because the book's exact wording was checked only against secondary quotations of it, which agree with each other.
5. Toulmin, S., The Uses of Argument (Cambridge University Press, 1958; updated ed. 2003), pp. 97 to 102, via Hitchcock, D., "Toulmin's Warrants" (ISSA, 2002/2003): the layout of claim, data, warrant, backing, modal qualifier ("presumably"), and rebuttal ("unless"), with the Harry example. As recorded in this course's SOURCES.md.
6. Groarke, L., "Informal Logic", Stanford Encyclopedia of Philosophy, sec. 4.1. The ARS conditions that lesson 7 teaches as ARG: "premises are acceptable when they are true or acceptable in some other way; relevant when they provide some (i.e. any) support for the conclusion of the argument; and sufficient when they provide enough support to warrant its acceptance." Following Johnson and Blair.