Preliminary Meta-theoretical Remarks
In the next section I will define and explain precisely what is meant by modal pluralism and normative pluralism. But first, I will describe the pattern of the argumentation in a formal sense independently of any particular understanding of the theoretical terms used. I will show how modal pluralism and normative pluralism are related to each other and to the theories of analysis and appraisal.
Does modal pluralism require normative pluralism? I will concede that there is modal pluralism. I will concede that there is normative pluralism, at least for the sake of argument. What I am denying, then, is the connection between them; namely that normative pluralism is required by or follows from modal pluralism. A plurality of modes--even of modes that are not reducible in all respects to a single mode-is not incompatible with a single norm.
Does this prove the falsity of normative pluralism? No, I have already conceded that normative pluralism may be true. To prove the compatibility of modal pluralism and normative monism is not to prove that there actually is a single norm, even if the plurality of modes is conceded. The main thing that I want to achieve is to prove that incompatibility does not follow from certain arguments and examples taken to demonstrate it. I wish to show that the burden of proof is still on those who wish to move away from the traditional view where the norms are those of logic, typically of ordinary propositional, deductive logic. (I leave to one side the possible issues of how normative pluralism relates to logical pluralism, i.e., the existence of multiple logics such as default and paraconsistent logics).
There are two theories that might be thought to require improvement: the theory of appraisal and the theory of analysis. The task of a theory of analysis is (as it always was) to sort out the appraisable from the non-appraisable and to put the appraisable into a form where it can be appraised. The task of the theory of appraisal is to appraise the appraisable. Having conceded that modal pluralism is true, a theory of analysis must account for it; that is to say that the theory must provide in principle for each mode to be analyzable into a form that makes it apt for appraisal. If it cannot, this may be an inadequacy in the theory of analysis or it may be an inadequacy in the theory of appraisal; it may mean that the theory of appraisal needs to be widened to allow in the appraisals that it seems intuitively that we make and that we want to make, in which case more things become apt for appraisal. If more things become apt for appraisal then this amounts to normative pluralism, for there must be more than one norm against which these modes can be appraised, and the theory of appraisal must account for all of them. However, if this is not so and the theory of appraisal does account for the appraisals that we make and want to make, then it is a problem for the theory of analysis alone. Nothing follows about the theory of appraisal, or in other words, normative pluralism does not follow from modal pluralism.
What is modal pluralism exactly? It is the claim that there are multiple modes of argumentation, and perhaps we should add, multiple legitimate modes of argumentation. What is a mode of argumentation? A locus classicus for discussion of modes of argumentation is Gilbert (1997). "An argument," Gilbert says, "may be said to be wholly or partially in a particular mode when its claim, data, warrant, and/or backing is drawn from that particular mode, or these items are communicated using a form of presentation from a particular mode" (p. 80). He goes on to distinguish four modes of argumentation: logical, emotional, visceral, and kisceral. An arguer has different means of putting his argumentative point across, of which the verbal assertion of a reason--what Gilbert calls the logical mode--is only one. To these modes we may add visual arguments, whose locus classicus is Birdsell and Groarke (1996) and is much discussed recently in informal logic circles.
It is not difficult to see or accept the general point. Sometimes, instead of a verbal exchange of reasons, we direct the attention of our opponent to something in the world that shows their standpoint or a crucial premise to be false. Sometimes we may bring about this falsity by our own actions. Sometimes we may bring about this falsity by undergoing or by not undergoing some psychological change, like having an emotional reaction. If we are giving directions, it is often better to draw a map than give verbal instructions. In short, we may direct attention to a piece of evidence without explicitly stating the evidence as a reason in speech, and it is frequently more efficacious to do so.
The kind of argument we normally deal with--the kind that we get from a written or spoken text, for example--is in the logical mode and can be appraised against logical norms. Gilbert's (2011) assertion is not so much that a logocentric theory of appraisal is incorrect, as that it fails to accommodate the complete range of legitimate argumentative moves, and thus should be treated as only one aspect of a pluralistic theory, rather than as the one and only approach to argument criticism. Adopting logocentrism as a monistic theory of appraisal privileges the logical mode and considers argumentative moves in other modes as illegitimate or fallacious. If this claim about privilege were true, and contrary to this claim, moves in non-logical modes are legitimate and appraisable, then Gilbert would be quite right to say that the logocentric theory of appraisal is inadequate and that we need a new theory that embraces different norms for different modes. However, I will argue that this is not so; non-verbal argumentative moves can be analyzed into verbal reason-giving moves provided that those moves are meaningful. Since it is these verbal reason-giving moves that are the inputs for appraisal, no further problems are raised for the theory of appraisal (whether monistic or pluralistic, whether logocentric or not) beyond those it may already have. No special problems arise because of the non-verbal nature of non-verbal argumentative moves and a logocentric theory of appraisal does not need to deny their legitimacy as evaluable argumentative moves.
What is normative pluralism? It is the view that there is more than one norm for argumentation, which is to say that there is no single definition of a "good argument." Opposed to normative pluralism is normative monism. The most common monistic view is deductivism. Deductivism claims that there is only one norm, one definition of a good argument: the only good argument is a deductively valid (and possibly sound) argument. Deductivism implies monism but monism does not imply deductivism.
Gilbert argues that having more than one mode (in particular, modes that are not verbal exchanges of reasons) means having a pluralistic, disjunctive theory of appraisal in which the mode must be identified first and a norm applied afterwards. From this perspective, argumentation must always be appraised as a process pursuing many distinct goals as opposed to one goal (that pursued primarily in the logical mode) taken as definitive of argument and thereby dictating a priori what the product should be and how it should be appraised. This a priorism comes from privileging just one goal-rational persuasion-as the goal or function of argument and then defining argument quality in relation to that goal. This will tend to lead to a monistic theory of appraisal.
There are two reasons the claim that modal pluralism requires normative pluralism is important. Firstly, it might lead the theorist in the wrong direction by giving herself unnecessary tasks that possibly distort the proper analytical tasks resulting from the division of labor between the two theories. Secondly, there is a trend in argumentation theory for going beyond the recognized canons of logic for the analysis and evaluation of arguments in their natural habitat. I wish to show that this is not as well motivated as its proponents would like to think; the arguments often given do not support it and in the process often misrepresent deductivism. Gilbert's (1997) arguments are one facet of a much wider antagonism towards formal logic and especially deductivism. Hence, I tend to defend deductivism but I am not committed to deductivism (I am quite happy, for instance, to concede that there are good inductive arguments of the "[A.sub.1] is B, [A.sub.2] is B, ... ; therefore, all A's are B" kind. I am inclined to count statistical syllogisms of the "Most A's are B, This is an A; therefore, [probably] this is a B" kind as deductive, however). The point is not so much to deny normative pluralism but to deny the particular kind of pluralism that has been claimed to follow from modal pluralism. If there is normative pluralism, it follows from considerations apparent from the logical mode alone, and not because of non-logical modes.
GILBERT'S ARGUMENT AGAINST PRIVILEGE
In this section, I intend to lay out Gilbert's (1997) explanation of how the logical mode becomes privileged. To persuade rationally is to give reasons. Only in the logical mode (and not in other modes) arguers state reasons in support of their thesis, and argumentation in this mode can be translated into a formal argument with only the customary problems of resolving ambiguous and vague formulations. The function of argumentation is rational persuasion. Therefore, all legitimate argumentation is in the logical mode and to evaluate it is to assess the strength of the reason's support for the conclusion. Then, because rational persuasion is, by definition, considered by the analyst to be the goal of argumentation, the argument is appraised against whatever norms might be countenanced in the...