6 A Dialogic Exercise

This chapter is written in a favourite form of mine, that of the philosophical dialogue. I continue to enjoy writing philosophical dialogues; most of these are either about social issues (revenge, tolerance, offensive speech) or the views of historical philosophers (Kant, Condorcet, Diderot, Locke). Looking back, I find myself rather amazed that I used this form for this material. Prima facie, the fit would seem poor. The participants explore two perspectives on argument analysis. Charmides takes the view that its point, even when one is focused on a particular argument, is to discover whether the conclusion of that argument is true. If one is inquiring into that subject, further claims, evidence, and inferences are relevant to one’s inquiry; one will therefore feel free to augment a particular argument so as to improve it and provide stronger reasons for the conclusion. From that perspective, strong charity may be defended; one seeks a strong case to explore the best support for the conclusion whose truth one is investigating. Charmides is defending what some have more recently called ‘steelmanning.’ Reconstruction should be generous and can be ambitious. The second perspective, that of Lysis, is narrower: one attends to a particular argument to consider its merits as an argument put forward by a particular arguer. One is exploring how well the proffered premises support the proffered conclusion in this argument by this arguer. The arguer’s likely knowledge and beliefs should be taken into account when one seeks to understand the argument; understanding it is a necessary prelude to assessing it. Lysis urges against Charmides that a person evaluating an argument should not assume an obligation to fix up the argument first, especially given that she is likely to fix it up according to her own standards and thereby distort the original.

In this dialogue, I sought balance between the two perspectives. My own perspective is closer to that of Lysis, a fact which may emerge in the dialogue itself and which surely emerges in subsequent chapters here and in the various editions of my textbook, A Practical Study of Argument.

Reading this dialogue again, my thoughts turn naturally to a question not explicitly raised here; that concerns dialogue models of argument. These models are popular and have been endorsed by Frans van Eemeren, Rob Grootendorst, Erik Krabbe, Douglas Walton and many others. They have been challenged by some, including J. Anthony Blair and myself. Blair, in “The Limits of the Dialogue Model of Argument,” (1997) points out that there are plenty of arguments that are not put forward in dialogue settings. A person, solo, presents a case in a book, scholarly article, or letter to the editor. In expressing his case, this person should ideally consider how others may respond to it, and may seek to consider possible objections to it. But he and he alone, working solo, has the power to construct and select possible objections; there is no one else with whom he is interacting and responding. Argument should be dialectical in the sense that likely or potential doubts and disagreements are taken into account in constructing the argument. But that is not to say that they are dialogical in the sense of being a turn-taking exchanges. Blair urges that we draw a clear distinction between ‘dialogical’ and ‘dialectical’. I agree.

Blair does not emphasize, as I would myself, that those who favour dialogue models typically construct the dialogue themselves. The supposed opponent is not real; often the proponent is not either. The dialogue is a constructed model and one that does not reflect that real context of many real arguments. In “When They Can’t Talk Back” (1999), I argued that the dialogue model is distorting for the many cases in which arguments are put forward in contexts where interaction between the arguer and her critics is impossible.

In the present dialogue, one may say that the only real arguers are the authors whose arguments are quoted and subject to analysis by the characters Charmides and Lysis – that is to say F. Chatelet, Hugh Lafollette, R.L. Gregory and J.G. Wallace, C.S. Peirce, C.W. Lewis, and Janet Keeping; their arguments provide data examined here. The constructed characters Lysis and Charmides analyze and evaluate that data (first level arguments). Their accounts, being about the first level arguments, are on a second level. Lysis and Charmides discuss their style and principles of argument analysis and evaluation. The dialogue itself is about their accounts and is thus on a third level. Accordingly, you might call this a meta-meta-discussion. No one is genuinely in dialogue, in the sense in which being in dialogue means being engaged and interacting with another person with opposed views. The exercise has all been constructed, solo, by a single author: myself. This absent personage has selected all the data and has constructed the norms and claims of both of the perspectives that are portrayed as having interacted (though they never really did). At this point reader’s eyes may glaze and heads may ache, as the mind starts to ponder post-modernism and its themes. I assure readers that I knew nothing of post-modernism when I wrote this (fictional) dialogue.

As mentioned, my own textbook is written from a perspective close to that of Lysis. In contrast, a recently successful book Reason in the Balance (first edition 2010) by Sharon Bailin and Mark Battersby proceeds from a perspective similar to that of Charmides. Bailin and Battersby urge that students learn to carefully examine an issue in order to come to a reasoned judgment about that issue. Students will be enabled to go beyond analysis of individual arguments, though fairly standard material of argument analysis and evaluation is provided in the work. One’s goal when reflecting on the merits of arguments is to find out whether conclusions (about a given issue) are true or not. Students’ attention is directed not to the question of what this or that person may have claimed and reasoned in her presented argument, but rather to the question of whether her proffered conclusion is true. The authors urge that students should employ a constructive, open-minded, yet disciplined inquiry toward that end. Dialogues presented in the work are realistic, though not real. As in the solo case, persons constructing the dialogues retain the freedom to consider those objections and counter-proposals that they select.

I hope the unorthodox form of this chapter does not make it difficult to read, and I urge readers to consider some emerging questions. Is it desirable that participant and spectator roles of argument assessment presume the same norms? Is it more charitable to attribute problematic premises than questionable inferences to an arguer? And inside every poor reasoner, is there a good reasoner struggling to get out?

---

LYSIS: What’s this all about, Charmides?

CHARMIDES: What’s what all about, Lysis?

LYSIS: This business of trying to analyze and evaluate other people’s arguments? What do we do this for, anyway?

CHARMIDES: The answer should be painfully obvious. We study arguments with a view to finding out whether their conclusions are true. In many contexts it is really important to know what is true or probable. A very basic way of showing that a claim is true or probably true is to justify it using a good argument. We study arguments because we seek the truth.

LYSIS: Do you really think so? My idea is that we evaluate other people’s arguments to see whether they have given good reasons, enough to convince us of their views. We aren’t just looking to see whether their conclusion is true or not. We want to see how well the conclusion has been supported. After all, we sometimes find poor arguments for conclusions we know to be true and even, occasionally, good arguments for conclusions we know to be false. Anyway, if our primary concern were to discover whether a conclusion were true, I think that analyzing other people’s arguments would be a pretty indirect way of doing this.

CHARMIDES: No it wouldn’t. What’s your model of directness anyway? There’s no way of directly investigating a hard question all by yourself. You have to approach the truth by looking at what other people have to say. You look at their arguments and by appraising these, you can get the best estimation of whether the conclusions they state are true or not.

CHARMIDES: Well really, Lysis, this is all beneath discussion. Of course that’s what I try to do, and that what any rational person would do. You have to use charity when you interpret an argument, especially when people don’t say all they have to say. You will often find arguments that are not very good or that seem incomplete or unclear in some way. And then you can fix these up, by adding a premise or several premises that are true, and plausible, and will improve the argument. Then you should add these, interpreting the arguments so as to make them as sensible as you can. All this is obvious and necessary because you are seeking truth. By reconstructing an argument you can best determine whether its conclusion is true.

LYSIS: I don’t understand why you find this all so obvious. To me it is just false. You see, I study arguments to see whether there are good grounds given for the conclusion. I don’t keep my attention fixed on the general question of whether the conclusion is true or could be shown true by some argument other than the one I am studying. I focus on the direct and immediate question of how well the conclusion is supported in the actual argument I am considering, the argument that has been stated.

You know, this makes argument analysis a much more viable and manageable task than it is on your view. You see, if someone omits considerations pertinent to his case, or relies on an inference that is hasty or unclear, then on my view that person has offered an argument which is inadequate. The argument should not rationally persuade anybody, because the reasons given don’t fully support the conclusion. That is the end of the story, so far as the analysis of this particular argument is concerned.

Now if you want to go further, and ask whether the conclusion might be true for some further reason, not given by the arguer, or whether some new information could be added to the original reasons, and would justify the conclusion, you can of course do this. Nobody is stopping you. But why say it’s argument analysis? You are not evaluating the original argument any more. Instead, you are embarking on an independent quest for knowledge. It just confuses things if you try to identify this task with that of argument interpretation and appraisal.

I like to keep life lean, spartan, and simple. If someone gives me a good argument, fine. If he doesn’t, I look at what’s there, find the holes in it, and state my reasons for seeing it as unsatisfactory. None of these fancy charitable fillings for me!

CHARMIDES: But really, this is too uncharitable to be correct! Don’t you think that extra filling is ever necessary? Why would we even mention the problem of missing premises if there were no missing premises? People do, after all, omit necessary steps from their arguments, sometimes because the arguer deems these truths too obvious to be worth stating, sometimes because they are so controversial the arguer would rather you didn’t notice them, and sometimes because the arguer does not realize they are required. Or sometimes out of sheer carelessness. When we do this, it is our moral responsibility as critics to fill in these gaps. Your kind of criticism will amount to nothing but hasty nit-picking. You won’t get even to the stage of understanding other people’s arguments, much less criticizing them, unless you add the required connecting links.

LYSIS: But, my charitable friend, how charitable are you being right now? Why do you not fill in some plausible intermediary steps in my case, if you think it fails to hold up? Practice what you preach, I’d say. Seriously, though, I do agree that occasionally arguments have missing premises. We need to supplement sometimes, but this is only legitimate when we have some basis for believing that the missing premises are, or would have been, accepted by the author of the argument. After all, you know, the discovery of missing premises is not like the discovery of early human fossils. Missing premises are not buried logical objects. Sometimes I think they are more like frustrated expectations. They are found not in any logical earth, but in the active mind of a critic.

CHARMIDES: So, the ontology of discourse – quite the metaphysical theme! And these are quite the metaphors! But really, you know, we already to have to read in a very considerable amount of background information just to understand words and grammatical relations, and the point of the argument, and the significance of facts. People are always active when they understand what is written or spoken, and they always have to bring in information that is not explicitly stated. Given that this is necessary all the time, I can’t see why you suddenly want to be so literal-minded so far as missing premises are concerned. Of course we often need to fill in people’s arguments, in order to make them sensible and plausible. This is charitable, reasonable interpretation, and it’s done in the interests of the fair and efficient pursuit of truth.

LYSIS: Well, I do agree that we sometimes have to resort to supplementing an argument with additional premises. What really bothers me about your view is not the idea that premises could be missing but the fact that it is charity which will provide some guidance on when to add premises and which ones to add. Your approach seems to ignore the very obvious fact that there are often differences between an arguer’s ideas and beliefs and those of the critic. When you say the critic should be charitable, this all sounds very nice, but the critic may well read in things that he thinks are improvements and by doing so, change the original argument so that it is more his own than that of the author. Surely we should only add premises the arguer would have agreed with, or at least only those that he is logically committed to. A fringe benefit of my approach is that it saves an awful lot of work.

Fundamentally, though, the reason for it is that it keeps us from taking flights of fancy on the wings of other people’s thoughts. Call your own arguments your own. Don’t go reading them into the work of everybody else. This is misplaced charity and won’t help you understand anyone.

CHARMIDES: My good friend, this approach seems most pedantic. What matters, fundamentally, is our quest for truth. What is pertinent to the truth is not whether this or that arguer in fact held this or that belief or used these exact words or some slightly different ones. It is not the arguer and his or her beliefs at all. It is the argument. Even though every argument is put forward by some person or other, it does not follow that every argument is inseparable from its author, bound to him or her forever by logical ties of ownership. The argument, once given, is a set of statements in the public domain, and for the purposes of systematic rational thought, it is this argument which is interesting. Who cares what its particular author might have happened to believe? Usually he or she is far away, and quite often they’re even dead.

LYSIS: You started out as though you, and not I, were the charitable, sympathetic critic. You, not I, were the one who would seek the most sympathetic and careful interpretation of what people have to say. Yet now you are telling me to forget about the arguer, who put forward the argument in the first place, and push relentlessly ahead toward some abstraction called ‘the truth’. You seem to be saying that one can best appraise other people’s reasoning by forgetting the other people. One can ignore these people and ignore their beliefs. I say, when it comes right down to it, this approach of yours is thoroughly disrespectful. And it is incoherent as well. If there are reasons to attend to the arguments other people present, then attend to those arguments that those people present. If there is no reason to attend to those arguments, just ignore them, or take their premises as data to be added to your general pool of information. You proceed and make up your own arguments. In a curious way, I think my hard line approach actually shows more respect for the ideas of others than your approach. Better to have been understood and rejected than never to have been understood at all.

CHARMIDES: You are begging the question, my friend. You say that you understand a person’s reasoning if you stick very closely to his or her stated premises, and you only add premises if you can give good evidence that the arguer either believed them or is logically committed to them. You imply that I do not understand that reasoning, when I add material, in order to fill out what is explicitly there. But this is just the issue, isn’t it? What is it to really understand someone’s arguments? That is the issue. It’s completely tendentious for you to insist that what you do gives genuine understanding and what I do does not. Arguers usually intend to give good rational support for their conclusions, and any arguer would be pleased to have plausible or true supplementary premises added to an argument by the critic.

LYSIS: Well maybe I did beg the question, but you just equivocated. Of course it’s true that most arguers intend to offer a good argument, but what this means is that when they do offer some specific argument, they regard this specific argument as a good one. What it doesn’t mean is that they intend to offer just that argument which you regard as a good one. What they offer they see as rationally adequate but they don’t necessarily intend to offer that which you see as rationally adequate. I won’t say you created an intentional confusion here, but you are surely confused about intentions.

CHARMIDES: We don’t seem to be getting very far in this dispute. I guess our two approaches would differ most for what, on the face of it, look like bad arguments. Here I would be inclined to charitably add, and you would be inclined to reject.

LYSIS: Right. When both these approaches are so easy to rationalize you can see why people disagree so much about fallacies.

CHARMIDES: I suppose. But that’s another problem. Why don’t we both do the best we can to construct a policy on missing premises and then we can apply our policies to the same examples? We can see what results we get, and then we can continue our discussion in a more concrete way.

LYSIS: All right. But where will these examples come from? Will we know enough about all the subjects to be able to appraise them sensibly?

CHARMIDES: It’s strange, but I have this feeling that we are being guided by an external force. When we are made aware of them, we will at the same time be told enough about the immediate contexts in which they were used. Thus we will be able to understand them.

LYSIS: Goodness, that is peculiar. Well, I hope you are right. We shall work for a week and then meet again to compare our results. I’m sure you’ll see that my policy is much more streamlined and efficient than yours, and much more true to arguers’ actual reasoning.

CHARMIDES: And I’m sure you’ll see that mine is much more fair and leads more quickly to the truth.

LYSIS: See you in a week then.

1. Charmides‘ Proposal on Missing Premises

1. To say that an argument has missing premises is to say that it has inference gaps. The conclusion does not emerge from the stated premises as it should in the type of argument given.

2. When we find such an inference gap in an argument, we should try to fill it. The original arguer could not have intended the argument to work as stated, because human reason does not aspire to create gappy arguments.

3. Gaps should not be filled by statements of general methodological principles, because that just means a gap has been misidentified. Nor should they be filled by a statement of the conditional associated with the argument, or a generalization of that conditional. Those would be reiterative and useless additions.

4. The main point in adding premises is to improve the original argument. Missing premises should be selected so as to fill identified inference gaps and so as to be either true or plausible.

5. Since not all good arguments are deductive arguments, proper addition of premises will not necessarily make a reconstructed argument deductively valid. It will, however, make it an inferentially correct argument of some type. With proper reconstruction, there are no fallacies in the sense of arguments involving inference errors, though there are many nondeductive arguments.

2. Lysis‘ Policy on Missing Premises

1. To say that an argument has missing premises is to presume that it has inference gaps. That is to say, the inferences we need to make in order to reason correctly from the premises to the conclusion do not go through as they should.

2. When we find a gap in an argument we may, under some conditions, attempt to fill it by inserting extra premises. However, we should not always do this when we find a gap, and we should not be too confident in doing it. The original arguer may have intended the inference to go through just as the argument is stated, and he or she may have different standards for inference than ours. Adding may distort the original argument that was put forward.

3. There are critically useless ways of filling gaps and these should not be employed even when we do decide that gaps have to be filled somehow. It is redundant to fill gaps with statements of general methodological principles. It is reiterative and critically useless to fill them with the associated conditional, a statement with the conjunction of the premises as its antecedent and the conclusion as its consequent. Nor should we use a generalization of the associated conditional.

4. It is the author’s beliefs, intentions, and logical commitments as expressed in the discourse in which the argument appears that give proper guidance for missing premises. If we are to insert any missing premise, we must be able to give good reasons to show that the arguer accepted this claim when the argument was made or that he or she was logically committed to it by other things actually stated. No premises should be inserted that are inconsistent with stated premises or with the conclusion, and none should be added which make any stated premises redundant from a logical point of view.

3. Results of the Exercise

Case One

. . if the perception of wax appeared to me more precise and distinct, after that not only sight and touch, but many other cases besides, rendered it manifest to my apprehension, with how much greater distinctness must I know myself, since all the reasons that contribute to the knowledge of the nature of wax, or of any body whatever, manifest still better the nature of my mind?  (Descartes, from Meditation ll; as quoted in The Rationalists (New York: Anchor Books, 1974), pp. 126 – 7. Translation by John Veitch.)

(Here Descartes is trying to show that, contrary to popular opinion, the mind is better known than physical things. He has just claimed that any judgment that a physical thing such as a piece of wax, exists, commits the subject to a judgment that he himself exists, and that this judgment about his mind is known with greater truth and certitude than the judgment about the physical object.)

 

Stated Premises and Conclusion

1. Sight and touch and many other things make wax manifest to my apprehension when I perceive it.

2. All the reasons that contribute to the knowledge of wax or any other body contribute even better to the knowledge of my mind.

3. Even if I appear to know a body such a wax precisely and distinctly, I know my mind much more distinctly.

LYSIS: I know that this man Rene Descartes acquired a great reputation, and that he worked out some marvellous theories. But even though this feeling is working in me, I can’t see this particular argument as a very good one. First of all, premise (2) is quite implausible. Secondly, there is an inference gap because this premise speaks of contributing to the knowledge of the mind, whereas the conclusion is about the distinctness with which the mind is known. Knowing more facts about the mind wouldn’t necessarily mean knowing the mind with greater distinctness, because distinctness is a matter of differentiation, and when the facts in question are to come from the mind’s knowledge of other things, there is no obvious way they could contribute to this differentiation. There isn’t really any basis in Descartes for filling in this gap. So we should just recognize that the gap exists and that he has given us a poor argument, with both a very implausible premise and an inference gap.

CHARMIDES: I differ. This fascinating argument must have been part of something very important. As it stands, it isn’t very clear, but it can be filled out so that the conclusion will be strongly supported inferentially by fairly plausible premises. There is an inference gap in the argument. We need to relate the greater number of contributions to knowledge that we have regarding the mind, according to premise (2) to the greater distinctness alleged for knowledge of the mind in the conclusion. What we need to do is construct a missing premise which will be as plausible as possible and will connect (1) and (2) with (3) in the most logically acceptable way. Descartes himself may have been a deductivist, but I still think that the most plausible link is going to be less than deductive. Having a greater number of facts about an item does not mean knowing it with greater distinctness. It is most reasonable to say that it will generally go along with knowing it with greater distinctness. Because there could be exceptions – as when if a thing had one and only one feature which defined it uniquely and you could know it with absolute distinctness by knowing only this one thing. The argument has a missing premise. It is:

MP1: In having more contributions to knowledge about one thing than another, I generally know that thing with more distinctness than I would know the other.

When this extra premise is read into the argument, we can see that there is some inductive reason for Descartes’ conclusion, granting of course his original premises. There is still a problem: the problem that the second premise needs defense, and a thorough reconstruction would add more reasons to support that as well. But we are only working on inference gaps right now, we are not supposed to do anything about the need for subarguments to support premises.

Case Two

Our degree is not recognized, but we have more students than ever. They come because they think they might learn something. Sure there are idiots. And I have given them credits. There are bigger idiots in the Government. Is it up to me to be more rigorous than the electorate? (Francois Chatelet, as quoted in the Canadian Association of University Teachers Bulletin for September, 1978.)

Chatelet was defending university professors in France against charges of irresponsibility and incompetence.

 

Stated Premises and Conclusion

1. Idiots have been given credits by faculty members teaching in universities.

2. There are even bigger idiots in the government.Therefore,

3. University faculty are not to be criticized for giving credits to idiots.

LYSIS: This person can’t have been nearly so famous as Rene Descartes, even though he seems to have the same nationality. This example is a straightforward instance of a fallacy of relevance. It seems to be a case of ‘two wrongs make a right’ reasoning. The author cites a deplorable fact in the second premise. He tries to infer from the claim that the so-called idiots in the government are even stupider than the so-called idiots in universities that university faculty should not be criticized. This is irrelevant reasoning, because standards for government officials have nothing to do with standards for universities. University faculty are supposed to pass and fail students according to proper judgments of those students’ competence in their areas of study. Government officials’ stupidity, even if it exists, has nothing to do with this. The argument is a gross non sequitur.

CHARMIDES: Now here is an argument which requires extensive supplementation. It is stated only briefly. Somehow the author believes that standards of competence indicated by the electorate are relevant to standards for credit given out by faculty members at universities. The problem is that we have to find a manner of supplementing the argument in order to express this intended connection in a plausible way, and we have to do this, making not only the inference link but the connecting statements plausible. Without such supplementations, the argument would look like a non sequitur. But from the very fact that it was given, we know the author thought government competence was relevant to the allotment of student credits. We have to make the connection. The whole argument may be set out like this:

1. Idiots have been given credits by faculty members teaching in universities.

2. There are even bigger idiots in government.

   MPl: The electorate, in tolerating these bigger idiots in government, indicates that community standards are tolerant of idiots.

   MP2: University faculty, in giving credits to idiots, indicate that they are tolerant of idiots.

   MP3: It is not the obligation of university faculty to be more rigorous in their standards than is the electorate.
   Therefore,

3. University faculty should not be criticized for giving credits to idiots.

The argument has three missing premises and should be reconstructed accordingly. The third missing premise is suggested by the rhetorical question in the original argument. The first and second missing premises are read in to make the stated material cogent. The argument has no fallacy, but its premises are controversial, especially MP3. We can surely judge that this premise is false. Faculty are awarding specialized degrees for which special qualifications are necessary. In addition, the second missing premise is not plausible, because even if it is a fact that government people turn out to be idiots, that does not show that people were willing to tolerate idiots when they first elected them. The argument is rather weak, because of these problems with its premises, but it is not a non sequitur or fallacy of any kind when it is properly filled in.

Case Three

Our society normally regulates a certain range of activities; it is illegal to perform these activities unless one has received prior permission to do so. We require automobile operators to have licenses. We forbid people from practicing medicine, law, pharmacy, or psychiatry unless they have satisfied certain licensing requirements.

Society’s decision to regulate just these activities is not ad hoc. The decision to restrict admission to certain vocations and to forbid some people from driving is based on an eminently plausible, though not often explicitly formulated, rationale. We require drivers to be licensed because driving an auto is an activity which is potentially harmful to others, safe performance of the activity requires a certain competence, and we have a moderately reliable procedure for determining that competence. The potential harm is obvious: incompetent drivers can and do maim and kill people. The best way we have of limiting this harm without sacrificing the benefits of automobile travel is to require that all drivers demonstrate at least minimal competence. We likewise license doctors, lawyers, and psychologists because they perform activities which can harm others. Obviously they must be proficient if they are to perform these activities properly, and we have a moderately reliable procedure for determining proficiency. Imagine a world in which everyone could legally drive a car, in which everyone could legally perform surgery, prescribe medications, dispense drugs, or offer legal advice. Such a world would hardly be desirable.

Consequently, any activity that is potentially harmful to others and requires certain demonstrated competence for its safe performance, is subject to regulation – that is, it is theoretically desirable that we regulate it. If someone has the requisite competence, then the action is not only subject to regulation but ought, all things considered, to be regulated. (From Hugh LaFollette, ‘Licensing Parents’, in Philosophy and Public Affairs, 1980.)

LaFollette uses this argument to introduce his major theme, namely that people should be licensed in order to become biological parents.

 

Stated Premises and Conclusion

1. Driving is licensed because it is potentially harmful and requires a testable competence.

2. Doctors, lawyers, and psychologists are licensed because they perform

3. A world in which anyone at all could drive, operate, prescribe drugs, or offer legal advice, would be very undesirable.
   Therefore,

4. Any potentially harmful activity requiring testable competence should be regulated, in the sense that regulating it is theoretically desirable.

LYSIS: This argument is a kind of hasty generalization. The premises provide an insufficient range of cases on which to base the conclusion, which is a universal one. The author seeks to ground a universal conclusion on a considerations of four kinds of activities. He fails to consider that these four may not be fully representative. In the context of his later use of the argument, this failure is very significant. The author uses this argument later to defend his idea that the biological parents of children should be licensed. But considerations of privacy, the human instinct to reproduce, and the harmfulness to individuals’ lives of any failure in society’s administration of judgments affect this case far differently than those cases cited by the author.

The argument as it stands fails, and not in such a way that it would require supplementary premises to back it up. The direction of the argument is clear. There is no inference gap: we can understand how we are supposed to connect the stated premises with the conclusion. Furthermore, there is nothing in the existing premises or surrounding text that could be used to construct any satisfactory missing premise even if we set out to look for one. The conclusion might be true, but the argument in support of it is hasty and weak.

CHARMIDES: There is a gap in this argument between the premises, as explicitly stated, and the conclusion. In order to support the conclusion with these premises, we have to make an additional supposition about the activities cited. It is a rather difficult matter to construct a plausible version of that supposition, since it is hard to see just what we need to assume about driving, doctoring, giving legal counsel, and giving psychological advice which makes these activities license a conclusion about all potentially harmful activities which require testable competence. We might add something like ‘Other activities that are potentially harmful and require testable competence are relevantly similar to these’. This is still a bit too open-ended and will be hard to verify, but we need something like this in order to fill the logical gap between the cases cited and the universal generalization. The argument becomes deductively valid when this premise is added, and its merits will depend on our appraisal of the added premise.

Case Four

…throughout Hebb argues that the position in the child is basically similar to that of the adult whose vision is restored at operation. Is this a tenable assumption? The adult, after all, has developed a ‘touch world’ which has served him well for many years, and which has become accepted as the principal vehicle of his occupational and social adaptation. The child, on the other hand, is concerned to develop a ‘visual world’ ab initio, and although tactile and motor activities contribute in an important way to its evolution, it is difficult to think of the two cases as in any real sense similar (From R.L. Gregory and J.G. Wallace, ‘Recovery from Early Blindness: a Case Study’, in Paul Tibbets (editor), Perception, (Chicago: Quadrangle Books, 1969), p. 385.)

Gregory and Wallace are arguing that it is a mistake to assimilate the case of an adult with a tactile-motor world but no visual world until an operation restoring sight with that of a child who is simultaneously constructing a visual world and a tactile-motor world on the basis of perceptual experience.

 

Stated Premises and Conclusion

1. An adult who recovers vision after years of blindness has had a touch world which has served him well for many years.

2. An adult who recovers vision after years of blindness has had a touch world which has become accepted as the principal vehicle of his occupational and social adaptation.

3. A child beginning to see is developing a visual world right from the start.

4. A child beginning to see does not have tactile sensations which constitute a coherent alternative touch world.
   So,

5. An adult who recovers vision after years of blindness is significantly different from a child developing visual perception.

LYSIS: This is a good clear argument. There are no inference gaps and it has no missing premises. The authors show that Hebb’s position was unreasonable.
CHARMIDES: This is a good argument, and the conclusion is adequately supported by the premises. Since the argument works as it stands, there is no need for any reconstruction using missing premises.

Case Five

The object of reasoning is to find out, from the consideration of what we already know, something else which we do not know. Consequently, reasoning is good if it be such as to give a true conclusion, from true premises, and not otherwise. (From C.S. Peirce, ‘The Fixation of Belief,’ in Pragmatism: the Classic Writings, edited by H.S. Thayer. New York: Mentor Books, 1970, p. 63.)

Stated Premises and Conclusion

1. The object of reasoning is to find out from the consideration of what we already know something else which we do not know.
   So,

2. Reasoning which gives us a true conclusion from true premises is good reasoning.
   and,

3. Reasoning that does not give us a true conclusion from true premises is not good reasoning.

LYSIS: This is an ambitious argument. The philosopher seeks two conclusions from a single premise. The problem is not with inference. It is that the premise requires clarification. If the word ‘know’ is understood too narrowly, the premise will be false, for the purpose of reasoning is also to form reasonable beliefs on the basis of other things which we have good reason to believe. However, since this philosopher was a fallibilist, he would likely have been willing to equate having good reason to believe with knowing. If this is done, the premise is all right. The direction of the argument is clear enough.

But just as we had to clarify ‘know’ in the premises, we have to look at the semantics of the conclusions. First we have to understand them as being about reasoning of a type; because if we don’t do this, (2) is vulnerable to counterexample. You can easily reason from a true premise to a true conclusion without employing good reasoning, just by being lucky. So we must understand that the references to reasoning are to general patterns of reasoning. Right after making this argument, Peirce goes on to speak of ‘habits of the mind’, so this interpretation has a good textual basis. However, there is still a problem with (3). Whereas (2), as explained here, can be inferred from (1) – reasoning has such-and-such purpose; reasoning of so-and-so type serves this purpose; therefore reasoning of so-and-so type is good reasoning, (3) cannot. The only way to make (1) true is, as we have seen, to understand ‘know’ in a flexible sense that would be suggested by Peirce’s fallibilism. On this interpretation of (1), (3) does not follow from (1), because reasoning might give us probable conclusions from probable premises, satisfying (1), but not (3).

Since this argument needs so much clarification, we can rightly accuse the author of vagueness, and since it can only work when ‘know’ is understood in two incompatible ways, we can also accuse him of equivocation. However, these problems do not generate inference gaps and the clarification needed is not to be supplied by extra premises.

CHARMIDES: This certainly is a challenging case. It doesn’t work very well as it stands, so something must be added to it to make it more clear. The argument is really about the purpose of reasoning, which Peirce specifies in (1). Of course here, we will get too limited a purpose if we understand ‘know’ in a restrictive way as requiring both solid justification and truth. So we shall have to understand ‘know’ more loosely, as including believing for good reasons. The point of the argument is that reasoning is good reasoning if and only if it serves its purpose, as stated in (1). The reference to reasoning in (2) and (3) must be understood as referring to reasoning of a type, for otherwise (2), at least, is too easily vulnerable to counterexample. The most elegant thing to do here is to turn Peirce’s passage into two separate arguments. The first:

1. The object of reasoning is to find out from the consideration of what we already know something else which we do not know.

MPl: Reasoning that gives us a true conclusion from true premises lets us find out something we do not know from something we do know.

MP2: Reasoning that serves its purpose is good reasoning.

So,