A "slippery slope argument" is a type of argument in which a first step is taken and a series of inextricable consequences follow, ultimately leading to a disastrous outcome. Many textbooks on informal logic and critical thinking treat the slippery slope argument as a fallacy. Walton argues that used correctly in some cases, they can be a reasonable type of argument to shift a burden of proof in a critical discussion, while in other cases they are (...) used incorrectly. Walton identifies and analyzes four types of slippery slope argument. Walton presents guidelines that show how each type of slippery slope argument can be used correctly or incorrectly, using over fifty case studies of argumentation on controversial issues. These include abortion, medical research on human embryos, euthanasia, the decriminalization of marijuana, pornography, and censorship, and banning of American flag burning. (shrink)

With the lack of progress there has been so far on climate change, some have begun researching the potential of geoengineering to allay future climatic harms. However, others contend that such research should be abandoned. One of the most‐cited reasons as to why research into geoengineering should be abandoned is the idea that such research sits at the top of slippery slope. The Slippery Slope Argument warns that even mere research into geoengineering will create institutional momentum, (...) ultimately leading to the deployment of a technology that is untested and perhaps morally objectionable. This article clearly lays out the Slippery Slope Argument against geoengineering research and analyses its premises. I claim that both the empirical premise – that research will inevitably lead to deployment – and the normative premise – that we have decisive moral reasons to avoid deployment – are questionable. The main conclusion of the article is that while we should be cognizant of the potential for research to lead to undesirable deployment scenarios, engaging in research need not necessarily lead inexorably to deployment. While insufficient to ground a moratorium on research, the Slippery Slope Argument points to the need for regulation and oversight in order to prevent undesirable deployment. (shrink)

It has been argued that geoengineering research should not be pursued because of a slippery slope from research to problematic deployment. These arguments have been thought weak or defective on the basis of interpretations that treat the arguments as relying on dubious premises. The paper urges a new interpretation of these arguments as precautionary arguments, i.e. as relying on a precautionary principle. This interpretation helps us better appreciate the potential normative force of the worries, (...) their potential policy relevance, and the kind of evidence required by slippery slope arguments. Understood as precautionary arguments, it is clear that slippery slope arguments against geoengineering capture concerns that are worth taking seriously. (shrink)

Slippery slope arguments are frequently dismissed as fallacious or weak arguments but are nevertheless commonly used in political and bioethical debates. This paper gives an overview of different variants of the argument commonly found in the literature and addresses their argumentative strength and the interrelations between them. The most common variant, the empirical slippery slope argument, predicts that if we do A, at some point the highly undesirable B will follow. I discuss both the (...) question which factors affect likelihood of slippage and the relation between the strength of the prediction and the justificatory power of the argument. (shrink)

I analyze three forms of the slippery slope argument (two logical and one empirical) using two questions: 1) in the context of what kind of norms are we considering a first step on a possible slope: statute law, precedent law, positive morality, or critical morality? 2) What is meant by "If we allow this first step"? The conclusion is that the argument's greatest force is in a context of institutionalized norms, like law, whereas its importance in morality (...) is only marginal. (shrink)

This article applies tools from argumentation theory to slippery slope arguments used in current ethical debates on genetic engineering. Among the tools used are argumentation schemes, value-based argumentation, critical questions, and burden of proof. It is argued that so-called drivers such as social acceptance and rapid technological development are also important factors that need to be taken into account alongside the argumentation scheme. It is shown that the slippery slope argument is basically a reasonable form (...) of argument, but is often flawed when used in ethical debates because of failures to meet the requirements of its scheme. (shrink)

Slippery slope arguments (SSAs) are used in a wide range of philosophical debates, but are often dismissed as empirically ill-founded and logically fallacious. In particular, leading authors put forward a meta-SSA which points to instances of empirically ill-founded and logically fallacious SSAs and to the alleged existence of a slippery slope leading to such SSAs to demonstrate that people should avoid using SSAs altogether. In this paper, I examine these prominent calls against using SSAs and (...) argue that such calls do not withstand scrutiny. I then identify several types of mechanisms leading to slippery slopes in real-life contexts to demonstrate that both the strength of SSAs and the justifiability of using SSAs are best assessed on a case-by-case basis. This result does not exempt the proponents of SSAs from the task of vindicating their use of SSAs. However, if correct, it undermines the often-made claim that people should avoid using SSAs altogether. (shrink)

In 1989, Susan Wolf convincingly warned of a troublesome consequence that should discourage any movement in American society towards physician-assisted death—a legal backlash against the gains made for limiting life-sustaining treatment. The authors demonstrate that this dire consequence did not come to pass. As physician-assisted suicide gains a foothold in USA and elsewhere, many other slippery slope arguments are being put forward. Although many of these speculations should be taken seriously, they do not justify halting the new (...) practice. Instead, our courts, regulatory agencies, journalists, professional organisations and researchers should carefully monitor and study it as it unfolds, allowing continuous improvement just as our society has done in implementing the practice of limiting life-sustaining treatment. (shrink)

This chapter contains sections titled: An Example The Paradigmatic Form of the Argument The Appeal to a Pernicious Precedent Slopes of Reason Slopes of Unreason Factual and Moral Plausibility Appearance and Reality References.

Slippery slope arguments are commonly thought to be fallacious. But is there a single fallacy which they all commit? A study of applied logic texts reveals competing diagnoses of the supposed error, and several recent authors take slippery slope arguments seriously. Clearly, there is room for comment. I shall give evidence of divergence on the question of what sort of argument constitutes a slippery slope, distinguish four different types of argument which have (...) all been deemed to be slippery slopes, and contend that two of these types need involve no logical error.We find in textbook accounts three quite differently oriented treatments of slippery slope: conceptual — relating to vagueness and the ancient sorites paradox; precedential — relating to the need to treat similar cases consistently; and causal — relating to the avoidance of actions which will, or would be likely to, set off a series of undersirable events. (shrink)

Daryl Pullman’s (2023) article purports to show that the increase and relatively high number of assisted deaths in Canada argues against the Canadian approach to medical aid in dying (MAiD)—similar...

Addressing the slippery slope argument (SSA) in legal contexts from the perspective of pragma-dialectics, this paper elaborates the conditions under which an SSA-scheme instance is used reasonably (rather than fallaciously). We review SSA-instances in past legal decisions and analyze the basic legal SSA-scheme. By illustrating the institutional preconditions influencing the reasoning by which an SSA moves forward, we identify three sub-schemes (causal SSA, analogical SSA, and Sorites SSA). For each sub-scheme we propose critical questions, as well as four (...) rules that clarify when the SSA scheme is used reasonably. The institutional preconditions make the analogical SSA expectable in common law contexts; the Sorites SSA is expectable in civil law contexts; whereas the causal SSA is common to both contexts. This result should inform future work on the identification of typical argumentative patterns for the SSA in legal contexts. (shrink)

We are often warned against stepping onto ‘slippery slopes’ — dangerously slick slides leading down to where the really bad stuff lies. But, as Arthur Miller here explains, these warnings often exaggerate the risk of a slip.

Slippery slope arguments (SSAs) are, so I argue, arguments from consequences which have the following peculiar characteristic: They take advantage of our being less than perfect in making—and acting according to—distinctions. But then, once SSAs are seen for what they are, they can be turned against themselves. Being less than perfect at making the second‐order distinction between distinctions we're good at abiding by and those we're bad at abiding by, we're bound to fail to make the (...) distinction between good and bad SSAs. One can therefore construct an SSA, the conclusion of which is, that we ought not to use SSAs. After characterizing SSAs and constructing the SSA against the use of SSAs, I then explore its implications. (shrink)

This article offers a logical analysis of Slippery Slope Arguments. Such arguments claim that adopting a certain act or policy would take us down a slippery slope to an undesirable bottom and infer from this that we should refrain from this act or policy. Even though a logical assessment of such arguments has not received much careful attention, it is of vital importance to their overall assessment because if the premises fail to support (...) the conclusion an argument is worthless. I partition slippery slope reasoning by means of two dichotomies (reasoning under certainty vs. uncertainty and one-step vs. multiple-step reasoning) into four general categories and evaluate these in turn. The analysis reveals that slippery slope arguments are logically fallacious. (shrink)

The Song and Ming dynasty Confucians make frequent use of what would today be identified as a slippery slope argument. The Book of Changes and its early commentaries provide both the language and the rationale for this argument, inasmuch as the Confucians regard these texts as a method for identifying tiny problems that will one day threaten the state. While today the slippery slope argument is often criticized for promoting an unreasoned resistance to change, a close (...) look at its use by Confucians reveals that they largely avoid this criticism, using the argument in a reasoned way to target not change, but excess. (shrink)

The standard problem with many slippery slope arguments is that they fail to provide us with the necessary evidence to warrant our believing that the significantly morally worse circumstances they predict will in fact come about. As such these arguments have widely been criticised as ‘scare-mongering’. Consequentialists have traditionally been at the forefront of such criticisms, demanding that we get serious about guiding our prescriptions for right action by a comprehensive appreciation of the empirical facts. This (...) is not surprising, since consequentialism has traditionally been committed to the idea that right action be driven by empirical realities, and this hard-headed approach has been an especially notable feature of Australian consequentialism. But this apparent empirical hard-headedness is very selective. While consequentialists have understood their moral outlook and commitments as guided by a partnership with empirical science – most explicitly in their replies to the arguments of their detractors – some consequentialists have been remarkably complacent about providing empirical support for their own prescriptions. Our key example here is the consequentialist claim that our current practises of partiality in fact maximise the good, impartially conceived. This claim has invariably been made without compelling support for the large empirical claims upon which it rests, and so, like the speculative empirical hand-waving of weak slippery slope arguments, it seems similarly to be undermined. While these arguments have presented us with ‘wishful thinking’ rather than ‘scare-mongering’, we argue in this paper that their complacency in meeting the relevant empirical justificatory burden remains much the same. (shrink)

Whenever some form of beneficent killing--for example, voluntary euthanasia--is advocated, the proposal is greeted with a flood of slippery-slope arguments warning of the dangers of a Nazi-style slide into genocide. This paper is an attempt systematically to evaluate arguments of this kind. Although there are slippery-slope arguments that are sound and convincing, typical formulations of the Nazi-invoking argument are found to be seriously deficient both in logical rigour and in the social history and (...) psychology required as a scholarly underpinning. As an antidote, an attempt is made both to identify some of the likely causes of genocide and to isolate some of the more modest but legitimate fears that lie behind slippery-slope arguments of this kind. (shrink)

One prevalent type of slippery slope argument has the following form: (1) by doing some initial act now, we will bring it about that we subsequently do some more extreme version of this act, and (2) we should not bring it about that we do this further act, therefore (3) we should not do the initial act. Such arguments are frequently regarded as mistaken, often on the grounds that they rely on speculative or insufficiently strong empirical premises. (...) In this article I point out another location at which these arguments may go wrong: I argue that, in their standard form, the truth of their empirical premises constitutes evidence for the falsity of their normative premises. If we will, as predicted, do the further act in the future, this gives us at least a prima facie reason to believe that the performance of this further act would be good, and thus something we should try to bring about. I end by briefly assessing the dialectic implications of my argument. I delineate a subset of slippery slope arguments against which my objection may be decisive, consider how the proponents of such arguments may evade my objection by adding further premises, and examine the likely plausibility of these additional premises. (shrink)

This paper attempts to debunk the slippery-slope argument against human germ-line gene therapy by showing that the downside of the slope – genetic enhancement – need not be as unethical or unjust as some people have supposed. It argues that if genetic enhancement is governed by proper regulations and is accompanied by adequate education, then it need not violate recognized principles of morality or social justice. Keywords: germ-line therapy, slippery slope argument, future generations, social justice (...) CiteULike Connotea Del.icio.us What's this? (shrink)

Any suggestion of altering the genetic makeup of human beings through gene therapy is quite likely to provoke a response involving some reference to a 'slippery slope'. In this article the author examines the topography of two different types of slippery slope argument, the logical slippery slope and the rhetorical slippery slope argument. The logical form of the argument suggests that if we permit somatic cell gene therapy then we are committed to (...) accepting germ line gene therapy in the future because there is no logically sustainable distinction between them. The rhetorical form posits that allowing somatic cell therapy now will be taking the first step on a slippery slope which will ultimately lead to the type of genocide perpetrated by the Nazis. The author tests the validity of these lines of argument against the facts of human gene therapy and concludes that because of their dependence on probabilities that cannot be empirically proven they should be largely disregarded in the much more important debate on moral line-drawing in gene therapy. (shrink)

In all great moral issues the moralist must choose and choosing has a price.

Although studies have yielded a detailed taxonomy of types of slippery slope arguments, they have failed to identify a basic argumentation scheme that applies to all. Therefore, there is no way of telling whether a given argument is a slippery slope argument or not. This paper solves the problem by providing a basic argumentation scheme. The scheme is shown to fit a clear and easily comprehensible example of a slippery slope argument that strongly (...) appears to be reasonable, something that has also been lacking. (shrink)

Biomedical research, on the one hand, contributes to important goals from generation of knowledge about the human body to the development and testing of therapeutics of all kinds. On the other hand, it can produce serious and sometimes unforeseeable consequences. In the ethical analysis of these two aspects of biomedical research, two important argumentative strategies play a major role. First, slippery slope arguments are used to warn of potential risks and to highlight knowledge-based limitations. Second, a dual-use (...) problem describes the challenge that already established techniques can be used for both morally wrong and morally right purposes. These two argumentative strategies appear to share several similarities, which will be investigated in this article. For this purpose, the article will first provide clear working definitions for both types of argument. This lays the foundation for the further ethical analysis. In a second step, and in order to investigate the similarities and differences of the argumentative strategies with an example from current ethical debates, CRISPR-Cas9, a currently very promising tool of genome editing, will be examined. The extent to which the possible applications of this genome editing tool can be addressed by slippery slope arguments or the dual use problem will be investigated. For this purpose, selected studies involving the use of CRISPR-Cas9 will be examined. Based on this two-step, analytic and example-based comparison of slippery-slope argumentation and dual-use considerations, the article will detail the ethically relevant difference between the two argumentative strategies and at the same time contribute to the ongoing ethical debate about CRISPR-Cas9. (shrink)

The argument from incremental differences among objects with indefinite property-Complement demarcations arranged along a continuum is known classically as the sorites or slippery slope fallacy. The inferences are typically unsound, And may contain structural logical defects, Though the precise source of error is the subject of wide-Ranging philosophical dispute. In this treatment, Slippery slopes are reduced to a single category of logically valid (but sometimes unsound) conditional chains of hypothetical syllogism. The analysis provides a framework for distinguishing (...) between unsound slippery slope sophisms, And logically valid semantically sound slippery slope arguments. (shrink)

Despite the fact that the reductio ad absurdum argument is a valid deductive form, while the slippery slope argument is most often presented as a fallacious form of inductive argument, the two argument types bear some striking similarities. Investigation of these similarities reveals some more universal difficulties in the teaching of informal logic, and, in particular the difference between strong informal arguments and fallacious ones.

This chapter provides empirical evidence about everyday attitudes concerning euthanasia. These attitudes have important implications for some ethical arguments about euthanasia. Two experiments suggested that some different descriptions of euthanasia have modest effects on people’s moral permissibility judgments regarding euthanasia. Experiment 1 (N = 422) used two different types of materials (scenarios and scales) and found that describing euthanasia differently (‘euthanasia’, ‘aid in dying’, and ‘physician assisted suicide’) had modest effects (≈3 % of the total variance) on permissibility judgments. (...) These effects were largely replicated in Experiment 2 (N = 409). However, in Experiment 2, judgments about euthanasia’s moral permissibility were best predicted by the voluntariness of the treatment. Voluntariness was a stronger predictor than some demographic factors and some domain general elements of moral judgments. These results help inform some debates about the moral permissibility of euthanasia (e.g., the slippery slope argument) suggesting that some of the key premises of those arguments are unwarranted. (shrink)

ABSTRACT This paper attempts to show that the acorn–oak tree argument against the slippery slope on the personhood of the fetus is valid and William Cooney's attack on this argument fails. I also argue that the slippery slope argument leads to on undesirable conclusion and should not be used as a valid tool in the debate on the personhood of the fetus.

Opponents of medically assisted dying have long appealed to ‘slippery slope’ arguments. One such slippery slope concerns palliative care: that the introduction of medically assisted dying will lead to a diminution in the quality or availability or palliative care for patients near the end of their lives. Empirical evidence from jurisdictions where assisted dying has been practiced for decades, such as Oregon and the Netherlands, indicate that such worries are largely unfounded. The failure of the (...) palliation slope argument is nevertheless instructive with respect to how slippery slope arguments can be appraised without having to await post-facto evidence regarding the effects of a proposed change in public policy. Close attention in particular to the norms operative in a given institution and how changes to policy will interact with those norms enable slippery slopes to be credibly appraised. (shrink)

Slippery-slope arguments typically question a course of action by estimating that it will end in misery once the first unfortunate step is taken. Previous studies indicate that estimations of the long-term consequences of certain debated actions, such as legalizing physician-assisted suicide, may be strongly influenced by tacit personal values. In this paper, we suggest that to the extent that slippery-slope arguments rest on estimations of future events, they may be mere rationalizations of personal values. (...) This might explain why there are proponents even for strikingly poor slippery-slope arguments. (shrink)

The article investigates the validity of two different versions of the slippery slope argument construed in relation to human gene therapy: the empirical and the conceptual argument. The empirical version holds that our accepting somatic cell therapy will eventually cause our accepting eugenic medical goals. The conceptual version holds that we are logically committed to accepting such goals once we have accepted somatic cell therapy. It is argued that neither the empirical nor the conceptual version of the argument (...) can provide a conclusive moral reason for banning somatic cell therapy. According to a third interpretation, referred to as the arbitrary result argument, the many apparent similarities between somatic cell therapy and eugenic-based human genetic engineering drive us to make principled choices concerning what differences and similarities between the two practices should be regarded as morally (ir)relevant. Decisions of this kind are likely to have unpredictable moral consequences. Thus formulated, the slippery slope argument has much plausibility. One objects to somatic cell therapy not so much because of what is at the bottom of the slope on which it lies, but because it is on a slope of which one does not know what is at the bottom. While the arbitrary result argument does not provide a conclusive reason for prohibiting human gene therapy, it reminds of a very important thing: when making bioethical decisions, we should be as specific and as consistent as possible about our basic moral and medical concepts. (shrink)

ABSTRACT Pharmacogenetics is a rapidly expanding area of research exploring the relationship between inter‐individual genetic variation and drug response, with the goal of developing genetically optimised therapies. Slippery slope arguments claim that a particular action should be rejected (or supported) because it might be the first step onto a slippery slope leading to undesirable (or desirable) consequences. In this article, several slippery slope arguments relevant to the context of pharmacogenetics are evaluated under (...) consideration of underlying reasons for their popularity. The author concludes that although the examined arguments are unconvincing as slippery slope arguments, they do matter in this context. While positive slippery slope arguments serve as a driving force to fuel the development of pharmacogenetics, their negative counterparts play an important role to sensitise policy makers and the public to potential problems. (shrink)