ISSA Proceedings 1998 – What Makes The Reductio Ad Absurdum An Important Tool For Rationality?

• by: Menashe Schwed - Ashkelon Regional College

This paper presents a summarized chapter from a study on the Reductio ad Absurdum, in which its logical, semantical and epistemological aspects are analyzed. I here focus on the neo-rationalistic motivation behind this research. The following analysis is only a partial report, in need of further study.
Traditional rationality is the quest for certainty and knowledge. It characterizes specific beliefs which are derived on the basis of appropriate reason and specific appropriate principles of assessment. The story of its failure is the story of the success of skepticism. One of the answers to the skeptical challenge on rationality is the conceptual shift from the notion of ‘verification’ to that of ‘refutation’. However, if refutation is understood as certainty regarding the falsity of the refuted, then this shift is only superficial, and does not solve the basic challenge. Certainty regarding a falsity is no less subject to the skeptical challenge than certainty regarding truth. My proposal to a solution to this problem is based on a modification to the common epistemological understanding of the Reductio ad Absurdum mode of argumentation. The key idea is to see refutation as conditional reasoning instead of absolute or certain, and to see rationality as focusing on the process of reasoning instead of its outcome.
The intense criticism on the notion of verification and the shift to that of refutation is best known through the work of Karl Popper. The paradigmatic examples of this shift, elaborated by Popper and his followers, pertain to science. The notion of refutation is, however, by far more problematic when it comes to philosophical controversies. There aren’t notions of crucial experiment and of fact of the matter in the non-empirical contexts of philosophical controversies, even in principle.
The Reductio ad Absurdum mode of argumentation is a basic logical tool in the procedure of refutation. The application of refutations to philosophical controversies must, therefore, account for the structure and function of the Reductio ad Absurdum. In a Reductio ad Absurdum, one starts by assuming the truth of a thesis ‘p’ (see first below). The meaning of the thesis ‘p’ is analyzed by way of deriving a series of consequences ‘q1’ to ‘qn’ implied by the assumed thesis. This clarification of the meaning of the thesis ‘p’ ends in the derivation of the consequence ‘a’. The consequence ‘a’ becomes an absurdity, however, in light of an external additional assumption regarding the truth of its negation ‘not-a’. The ensuing contradiction ‘a and not-a’ leads to the conclusion that the thesis ‘p’ is not true, namely that ‘not-p’.

I want to begin my suggestion with the following problem: From a logical point of view, every indirect argument scheme of inferring a conclusion from a given set of premises, such as the Reductio ad Absurdum, can be rephrased as a direct and constructive one. In what sense, then, is the Reductio ad Absurdum preferable to a direct proof that ‘not-p’ ? The Reductio ad Absurdum can be interpreted or understood in at least three ways, of which only one makes it preferable to a direct proof. Read more

ISSA Proceedings 1998 – Viciousness And Actual Infinity In Aristotle’s Infinite Regress Arguments

• by: Claude Gratton - University of Nevada

Aristotle sometimes presents an infinite regress argument without showing us how its infinite regress is derived, or why its infinite regress is vicious. An infinite regress is vicious if it entails either a false statement or an unacceptable consequence. Given his omissions, we sometimes hastily grant that there is an infinite regress, and that it is somehow vicious. In this paper I will not address the derivation of his infinite regresses, but simply assume that they are entailed, and focus my attention on their viciousness.
Aristotle’s notion of the infinite can appear to be involved in establishing the viciousness of an infinite regress in an infinite regress argument in the following way. An infinite regress entails the statement that (1) there are actually infinitely many entities. Given the extent to which he argues against the existence of actual infinities in his philosophical works[i] (especially in Book 3 of the Physics)[ii], it is reasonable to suspect that Aristotle tacitly uses the statement, (2) actual infinities do not exist, in the infinite regress arguments where he does not explicitly discuss the viciousness. The conjunction of these two statements shows that an infinite regress entails a false statement, and consequently shows that the infinite regress is vicious.
My goal is to suggest a different interpretation: we can establish the viciousness of most infinite regresses in Aristotle’s works without assuming that he tacitly uses the claim that actual infinities do not exist. The evidence that I will advance will not prove that my interpretation is the only one, but it will show that in some cases a closer fidelity to the texts obliges us to see that Aristotle’s objections against infinite regresses need not follow from his notion of the infinite.
I have a number of reasons supporting this interpretation. First, in the cases where Aristotle explicitly discusses the viciousness of infinite regress, he does not make use of that claim. These are found in the On Interpretation 20b32-21a7, Physics 225b34-226a6 and 242b43-53, On Generation and Corruption 332a26-333a15, Metaphysics 1006a 6-10 and1007a33-b3, Nicomachean Ethics 1094a18-22.
Secondly, in some cases where Aristotle doe not explicitly discuss the viciousness of an infinite regress, one can establish the viciousness without making use of his claim that actual infinities do not exist. I will describe different ways in which one can discover these alternative interpretations.

In some cases the infinite regress entails an easily identifiable implicit statement that is obviously false, and that is unrelated to Aristotle’s belief that actual infinities do not exist. Consider the following. Some hold that the soul is divisible, and that we think with one part and desire with another. If, then, its nature admits of its being divided, what can it be that holds the parts together? Surely not the body; on the contrary it seems rather to be the soul that holds the body together; at any rate when the soul departs the body disintegrates and decays. If, then, there is something else which makes the soul one, this would have the best right to the name of soul, and we shall have to repeat for it the question: Is it one or multipartite? If it is one, why not at once admit that the soul is one? If it has parts, once more the question must be put: What holds its parts together, and so ad infinitum (On the Soul 411b5-13).
The goal of this infinite regress argument is to reject the claim that the soul is divisible. If an infinite regress were entailed, it would consist of an infinite succession of unifying parts of a soul. A necessary condition for something to “have the best right to the name of ‘soul’” (411b10) is that it unify all the parts of a soul. Though each one of the infinitely many parts of the soul contributes to the unification of the soul, no single part by itself makes the soul unified. Hence, none of those part satisfies the sufficient condition. So, the regress entails the false (for Aristotle) statement that there is no soul.
A further infinite regress argument occurs later in the same book.
Since it is through sense that we are aware that we are seeing or hearing, it must be either by sight that we are aware of seeing, or by some sense other than sight. But the sense that gives us this new sensation must perceive both sight and its object, viz. color: so that either there will be two senses both percipient of the same sensible object, or the sense must be percipient of itself. Further, even if the sense which perceives sight were different from sight, we must either fall into an infinite regress, or we must somewhere assume a sense which is aware of itself. If so, we ought to do this in the first case (On the Soul 425b11-17). Read more

ISSA Proceedings 1998 – A General Theory Of Public Argumentation: Death And Rebirth?

• by: Bruce E. Gronbeck - The University of Iowa

For some time, coteries of philosophers, rhetoricians, social theorists, and various other students of public reasoning have thought and written about the possibility of resurrecting the presumably dead practice of rational public argumentation. They have sought, in the words of James Crosswhite (1996: 70), “not to expose [public arguments] for the wretched things they are, but to reveal the intrinsic hopes carried by the practice of argument.” They have pursued optimistic answers to questions that Michel Foucault (1993:18-19, qted. in Crosswaite 1996:13) asserts have been central to philosophy and critical thought since the eighteenth century: “What is this Reason that we use? What are its historical effects?
What are its limits, and what are its dangers? How can we exist as rational beings, fortunately committed to practicing a rationality that is unfortunately crisscrossed by intrinsic dangers?” More specifically, I have argued (1998) that most western general theories of argumentation have been grounded in understandings of specific relationships between knowers and the known:
* ideas as the contents of minds
* evidence as external to minds
* inference as grounded in both mental and linguistic operations, that is, as reflective of mental activity yet materialized in particular kinds of language use.
Those three epistemological assumptions were the foundations of the philosophy of science and then public argument theory that grew up in the nineteenth century (see Fuller 1993: esp. ch. 1), making argumentative discourse – a kind of logical talk – the link between the knower and the known, and hence the mechanism for reasoned decision making as it ought to occur in the worlds of all knowers from all eras of human existence.
Such assumptions have been under attack at least since Kant sought to collapse the Cartesian dichtomy between knowing and being and since Nietzsche declared the end of philosophy. Following World War I, there were concerted drives to save public, rational argumentation by eliminating fallacious reasoning (Lasswell 1928), by neutralizing and concretizing interpersonal talk[i], and by making the verifiability principle a weapon for distinguishing between sense and non-sense in all arenas of human affairs (e.g., Ayer 1936/1962). Read more

ISSA Proceedings 1998 – Innocence By Dissociation. A Pragma-Dialectical Analysis Of The Fallacy Of Incorrect Dissociation In The Vatican Document ‘We Remember: A Reflection On The Shoah’

• by: Rob Grootendorst - University of Amsterdam

1. Introduction
The Vatican document ‘We remember: A reflection on the Shoah’, (issued on March 16, 1998) has led to many critical reactions throughout the world. The main reason for this is that it did not contain the generally expected apology to the Jewish people for the Roman Catholic Church’s complicity in the Holocaust but, instead, turned out to be an apologia in which the Church pleads not guilty. The apologia is based on a twofold distinction:
(1) between the Church as an institution and its individual members, and
(2) between anti-Semitism and anti-Judaism.

In this paper, I argue that these distinctions both constitute the fallacy of incorrect dissociation. The concept of dissociation was introduced by Perelman and Olbrechts-Tyteca. It is one of the two main principles of argumentation they discuss – the other one being association. In pragma-dialectical terms, dissociation aims at changing one of the the protagonist and the antagonist’s common starting points. If this is not done properly, the dissociation constitutes a violation of one of the rules for critical discussion. In this case, I contend that Rule 6 has been broken because the document presents the distinctions as self-evident and is therefore guilty of begging the question.
In Section 2, I describe the historical background of the document and sketch its outlines. In Section 3, I summarize the main reactions to it. In Section 4, I explain why the two distinctions made in the document can be analysed as dissociations in the Perelmanian sense. In Section 5, I argue that these dissociations violate Rule 6 of pragma-dialectics and constitute the fallacy of ‘innocence by dissociation’, being a special case of the fallacy of incorrect dissociation. Finally, in Section 6, I conclude that this fallacy is the terminological counterpart of the well-known fallacy of ‘guilt by association’.

2. Background and outline of ‘We remember: A reflection on the Shoah’
‘We Remember: A reflection on the Shoah’ is a 14-page document issued by the Vatican Commission for Religious Relations with the Jews on March 16, 1998.[i] It is a long-awaited document because it addresses the role of the Roman Catholic Church in the Holocaust during the Second World War. The document acknowledges that individual Catholics did things that were wrong or even sinful in their support of anti-Semitism and of Nazi persecution of Jews, and it repents for this – using the Hebrew word teshuvah. But it also absolves the Church as such from complicity in the Holocaust. It even warmly praises the controversial wartime Pope Pius XII (who has long been accused of remaining silent in the face of Nazi genocide and even of pro-German tendencies) for saving hundreds of thousands of Jewish lives ‘personally or through his representatives’.
The Vatican commission took up the task of creating this document at Pope John Paul II’s request eleven years ago, in 1987 – a year after the pope had a historic meeting with Rome Chief Rabbi Elio Toaff in Rome’s central synagogue. It is the third formal document prepared by the commission, following the landmark Nostra Aetate declaration of 1965, which marked the first official gesture of reconciliation by the Church to the Jews by repudiating the concept of Jewish guilt for Jesus’ death and by calling for mutual respect and dialogue between Catholics and Jews. By the way, it was not until 1965 that the Vatican eliminated the phrase ‘perfidious Jews’ from the liturgy of the Holy Week service.
The Vatican statement takes pains to distinguish anti-Judaism from anti-Semitism, suggesting that only the Nazis were guilty of anti-Semitism. It also stops far short of taking responsiblity as a religious institution from promulgating the tenets of anti-Judaism, in particular the teaching that the Jews killed Jesus. The widely accepted view is that this central Christian teaching provided the theological foundation for the anti-Semitism of the Nazi years that culminated in the murder of six million Jews by the Nazis. Instead, the Vatican’s document distances Christianity from the Holocaust. ‘The Shoah was the work of a thoroughly modern neo-pagan regime,’ it says. Read more

ISSA Proceedings 1998 – Greek Mythic Conceptions Of Persuasion

• by: Mark H. Wright - Embry-Riddle University

In his provocative work, Protagoras and Logos, Edward Schiappa (1991) suggests that the Presocratics, the Sophists and Plato shared a different approach to language and communication. Still constrained to varying degrees by their primarily oral culture, they nevertheless offered prose as an alternative to poetry, and “treated language itself as an object of analysis for the first time in Greek history” (31). While Schiappa treats the definition and historical manifestations of logos with great care, he fails to do the same with mythos; presumably the Presocratics, the Sophists and Plato offered an alternative not only to “poetry as a vehicle of wisdom and entertainment,” but also to mythic accounts and conceptions of persuasion (31). Hence it is possible to better understand the contributions of early theorists of logos by better understanding the mythic understanding of persuasion that was available to the Greeks. In this essay I will explore the Greek mythic beliefs that persuasion took place through the action of the deities Hermes, Peitho, and the Charites (Barthell 1971: 152). After considering the range of meanings that each represents, I will consider the meanings represented by various combinations of them. In pursuing these meanings, I’m attempting to understand what a Greek, especially an Athenian, would gain by asking, “How can I persuade x?” and receiving the answer, “By considering Peitho, the Charites, and Hermes.” This question would have acquired more urgency around 500 BC, after Kleisthenes’ reforms, when the Athenian Pnyx was reinforced and dressed for the first time, hence dominating the approach to the marketplace (Kournouniotes and Thompson 1932: 216). After considering likely answers to the question, I will return to Schiappa’s argument, and maintain that Protagoras and later theorists where not as revolutionary as Schiappa portrays them, when one treats the mythic-poetic tradition as more than a preference for poetry.
In the discussions of deities that follows, it would be well to keep in mind the following chronology. The Iliad and the Odyssey date from the eighth century BC; Hesiod’s poems date from the seventh century BC; and the Homeric Hymns date from the sixth and fifth centuries BC. The Homeric Hymn to Hermes is from the sixth, probably late sixth century BC. Protagoras arrived in Athens around 450 BC.

1. Analysis of deities associated with persuasion
1.1 Hermes
Hermes probably originally arose as a god of the stone heaps that marked property boundaries (Farnell 1909: 7; Brown 1917/1990: 32). Hermes was the power found in the heap (Burkert 156). Because many tribal activities took place at the boundary between tribal territories, Hermes took on a range of associated meanings. Trading took place at the boundaries, so Hermes became a god of the marketplace, which later moved into the center of towns (Brown 1917/1990: 37). At first the stone heaps marked a neutral and sacred spot where trading could be safely conducted by traveling tradesmen and tribal groups with surplus goods (Farnell 1909: 26). Later, trading could safely be conducted in towns themselves. For example, in archaic Athens, the marketplace was on the northwest slope of the Acropolis, but was moved further north by Solon to a more central, level location (Travlos 1971: 2). At the symbolic center of the new agora was the altar of the Twelve Gods, and a Stoa of large herms (21). From that center, beginning around 520 BC, distances were measured and marked with herms at halfway points along all the major roads leading to the city (Brown 1917/1990: 107). The herms were inscribed with a statement of ownership by the tyrant Hipparchus, and a maxim such as “Think just thoughts as you journey” (Brown 1917/1990: 111; Parker 1996: 80). In this aspect Hermes implies that persuasion was a key to the success of the marketplace. Read more

ISSA Proceedings 1998 – Constitutive Rules And Rules Of Inference

• by: Jaap Hage - Maastricht University

1. Introduction
The notion of a constitutive rule was placed on the philosophical agenda by John Searle who opposed constitutive rules to regulative rules. Where ‘regulative rules regulate antecedently or independently existing forms of behaviour ….. constitutive rules do not merely regulate, they create or define new forms of behaviour. The rules of football or chess, for example, do not merely regulate playing football or chess, but as it were they create the very possibility of playing such games.’ (Searle 1969: 33).
If we take the notion of behaviour rather broad, to make it include not only physical, but also mental behaviour such as believing and making inferences, rules of inference can be considered as a kind of regulative rules. Rules of inference indicate what we are allowed to infer, and, in an epistemological context, what we are justified to believe, given our other beliefs. On this view, the distinction between constitutive rules and rules of inference is a special case of the distinction between constitutive rules and regulative rules.
In this paper I want to explore the distinction and the relations between constitutive rules and rules of inference. In section 2 I elaborate on the distinction between these two. In section 3 the distinction is exploited to explain the defeasibility of reasoning with rules of inference. In section 4 I will argue for the surprising view that propositional logic is in the first place an ontological theory, and only in the second place a theory of valid reasoning. The argument of section 4 is supported in section 5 with a sketch of the outlines of a general theory of valid reasoning. The paper is summarised in section 6.

2. Constitutive rules and rules of inference
The distinction between constitutive rules and rules of inference is based on another distinction, that is the distinction between the world and our beliefs about it. Let us follow Wittgenstein (1922, 1.1) in defining the world as the set of all facts. Facts are what corresponds in the world to true sentences. Since sentences are language-dependent, facts are also language-dependent. And so is the world, because the world is the set of all facts.
This view does not imply that the world depends completely on human culture, but rather that the world is captured by means of concepts that depend on human culture. The conceptual framework in terms of which the world is captured is a cultural phenomenon. That does not preclude the possibility that this conceptual framework has been adapted in time, e.g. through both physical and cultural evolution, to capture the world as well as possible.
The facts in the world are not independent of each other. There are physical laws that create law-like connections between facts of certain types. Physical laws should be distinguished from human attempts to describe them. These attempts form hypotheses that may be true or false. The laws themselves are not true or false, but exist or not. An example of a physical law is the law of gravitation. This law creates a connection between the facts that body 1 has mass m1, body 2 has mass m2, and that the distance between them is d, and the fact that between the bodies 1 and 2 there exists a gravitational force that equals _m1m2/d2, where _ is the gravitational constant. That the law of gravitation holds seems to be a fact about the world. This fact brings with it that other facts in the world are related in the way indicated in the law. Read more