Causal slippery slope arguments with moral conclusions are sometimes stronger than we think. Their strength may be missed either by overlooking the problems of human nature which support the arguments or, upon seeing the problems, by underestimating their influence upon human behaviour. This article aims to correct the oversight and the misjudgement by looking in some detail at four interrelated problems of human nature which have a direct bearing upon moral causal slope arguments.

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)

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)

A slippery slope argument is an argument to this twofold effect. First, that if a policy or practice P is permitted, then we lack the dialectical resources to demonstrate that a similar policy or practice P* is not permissible. Since P* is indeed not permissible, we should not endorse policy or practice P. At the heart of such arguments is the idea of dialectical impotence, the inability to stop the acceptance of apparently small deviations from a heretofore secure policy (...) or practice from leading to apparently large and unacceptable deviations. Using examples of analogical arguments and sorites arguments I examine this phenomenon in the context of collapsing taboos. (shrink)

A `slippery slope' argument in medical ethics is one that opposes itself to a new proposal on the grounds that it is not _per se_ intolerable but will lead to a situation that is. Lamb evaluates such arguments, demonstrating their centrality to the subject.

This chapter focuses on one of the common fallacies in Western philosophy called the slippery slope. According to Patrick Hurley in A Concise Introduction to Logic, “the fallacy of slippery slope is a variety of the false cause fallacy. It occurs when the conclusion of an argument rests on an alleged chain reaction and there is not sufficient reason to think that the chain reaction will actually take place”. The key term in the chapter is “chain reaction”. If (...) all of the events in the chain reaction can be justified, then the slippery slope is not committed. But the nuances and intricate improbable connections between each event still make it difficult to support the ultimate conclusion, which is to get rid of cable. The chapter discusses two simple techniques in order to avoid committing the slippery slope fallacy. (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 (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)

Agonist theorists have argued against deliberative democrats that democratic institutions should not seek to establish a rational consensus, but rather allow political disagreements to be expressed in an adversarial form. But democratic agonism is not antagonism: some restriction of the plurality of admissible expressions is not incompatible with a legitimate public sphere. However, is it generally possible to grant this distinction between antagonism and agonism without accepting normative standards in public discourse that saliently resemble those advocated by (some) deliberative democrats? (...) In this paper we provide an analysis of one important aspect of political communication, the use of slippery slope arguments, and show that the fact of pluralism weakens the agonists’ case for contestation as a sufficient ingredient for appropriately democratic public discourse. We illustrate that contention by identifying two specific kinds of what we call pluralism slippery slopes, i.e. mechanisms whereby pluralism reinforces the efficacy of slippery slope arguments. (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)

Michael Clark has recently argued that the slippery slope argument against voluntary euthanasia is ‘entirely consequentialist’ and that its use to justify continued prohibition of voluntary euthanasia involves a failure to treat patients who request assistance in ending their lives as ends in themselves. This article agues that in fact the slippery slope is consistent with most forms of deontology, and that it need not involve any violation of the principle that people should be treated as ends, depending (...) upon how that principle is construed. It is concluded that supporters of voluntary euthanasia cannot dismiss the slippery slope argument on the basis of deontological principles but must take seriously the consequences that it postulates and engage in factual argument about their likely extent and about the likely effectiveness of any proposed safeguards. (shrink)

I here discuss an argument frequently dismissed as a fallacy – the slippery slope or camel's nose. The argument has three forms – analogical, argumentative, and prudential. None of these provides a deductive guarantee, but all can provide considerations capable of influencing the intellect. Our evaluation of such arguments reflects our background social and evaluative assumptions.

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 argumentation features prominently in debates over assisted suicide. The jurisdiction of Oregon features prominently too, especially as regards parliamentary scrutiny of assisted suicide proposals. This paper examines Oregon’s public data (including certain official pronouncements) on assisted suicide in light of the two basic versions of the slippery slope argument, the empirical and moral-logical versions. Oregon’s data evidences some normatively interesting shifts in its assisted suicide practice which in turn prompts consideration of two elements of moral-logical slippage (...) that are not widely discussed. One is slippage from an initial autonomy-based public justification for assisted suicide which does not include burden-based concerns within its operative account of voluntariness to an evolved public justification that does. The other is an expansion of a terminal illness ground to include chronic illnesses effectively rendered terminal via a refusal of 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.

Our actions, individually and collectively, inevitably affect others, ourselves, and our institutions. They shape the people we become and the kind of world we inhabit. Sometimes those consequences are positive, a giant leap for moral humankind. Other times they are morally regressive. This propensity of current actions to shape the future is morally important. But slippery slope arguments are a poor way to capture it. That is not to say we can never develop cogent slippery slope arguments. Nonetheless, (...) given their most common usage, it would be prudent to avoid them in moral and political debate. They are often fallacious and have often been used for ill. They are normally used to defend the moral status quo. Even when they are cogent, we can always find an alternate way to capture their insights. Finally, by accepting that the moral roads on which we travel are slippery, we become better able to successfully navigate them. (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)

In response to the paper by Keown and Jochemsen in which the latest empirical data concerning euthanasia and other end-of-life decisions in the Netherlands is discussed, this paper discusses three points. The use of euthanasia in cases in which palliative care was a viable alternative may be taken as proof of a slippery slope. However, it could also be interpreted as an indication of a shift towards more autonomy-based end-of-life decisions. The cases of non-voluntary euthanasia are a serious problem (...) in the Netherlands and they are only rarely justifiable. However, they do not prove the existence of a slippery slope. Persuading the physician to bring euthanasia cases to the knowledge of the authorities is a problem of any euthanasia policy. The Dutch notification procedure has recently been changed to reduce the underreporting of cases. However, many questions remain. (shrink)

The article examines the so-called slippery slope argument (SSA) against the legalization of active voluntary euthanasia (AVE). According to the SSA, by legalizing AVE, the least morally controversial type of euthanasia, we will take the first step onto a slippery slope and inevitably end up in the moral abyss of widespread abuse and violations of the rights of the weakest and most vulnerable patients. In the first part of the paper, empirical evidence to the contrary is presented and (...) analyzed: None of the forecasted regrettable trends can be elicited from the body of existing statistical data. Accordingly, we have no good reason to believe either that we already are, or are sooner or later going to be, sliding into a moral abyss. A related question is then considered: Would it not be wiser and safer to stick to the status quo and preserve the existing legal ban on AVE even if the risk of its abuse is uncertain and may well turn out to be relatively low? It is argued that such an appeal to precautionary reasoning fails to justify an outright legal ban on AVE for at least two reasons: (i) it grossly underestimates the hidden moral costs of current legal arrangements (competent terminal patients suffer both disrespect for their autonomous will and deprivation of the good of a timely death) and (ii) the ban is both too inefficient and disproportionate to qualify as a reasonable measure of precaution. (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)

Slippery slope arguments appear regularly whenever morally contested social change is proposed. Such arguments assume that all or some consequences which could possibly flow from permitting a particular practice are morally unacceptable.Typically, “slippery slope” arguments claim that endorsing some premise, doing some action or adopting some policy will lead to some definite outcome that is generally judged to be wrong or bad. The “slope” is “slippery” because there are claimed to be no plausible halting points between the (...) initial commitment to a premise, action, or policy and the resultant bad outcome. The desire to avoid such projected future consequences provides adequate reasons for not taking the first step.Thus the legalization of abortion in limited circumstances is asserted to lead down the slippery slope towards abortion on demand and even infanticide; and the legalization of assisted suicide to lead inexorably to the acceptance of voluntary euthanasia and subsequently to the sanctioning of the practice of nonvoluntary euthanasia – even involuntary euthanasia of “undesirable” individuals. (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.

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)

Is the Nazi euthanasia program a useful analogy for contemporary discussions of euthanasia? This paper explores the logic of slippery slope arguments with the Nazi analogy as a test case.

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)

Among the questions facing the religious there is one that is becoming particularly pressing in our contemporary world of mingled cultures. Expressed as religious people sometimes put it to themselves, it is: How does my religion relate to other religions? There are two very different answers abroad. One is: mine is true and all others, to the extent that they depart from mine, are false and are to be rejected. The other is: mine is valid-for-me, and those of others are (...) valid-for-them. The first answer has the virtue of being utterly straightforward and not mealy-mouthed, but it seems parochial and myopic, for, as John Hick points out: In the great majority of cases, the tradition within which a religious person finds his relationship to the Real depends to a very great extent upon where and when he or she is born…In view of this situation, can one be unquestionably confident that the religion which one happens to have inherited by birth is indeed normative and that all others are properly to be graded by their likeness or unlikeness to it? (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.

A commentary on “Physician Assisted Dying: A Subtler Slippery Slope,” by Thomas Duffy, in the March‐April 2014 issue.

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)

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)

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)

'Fear' is used scientifically in two ways, which causes confusion: it refers to conscious feelings and to behavioral and physiological responses. Restricting the use of 'fear' to denote feelings and using 'threat-induced defensive reactions' for the responses would help avoid misunderstandings about the brain mechanisms involved.

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)

In a recent article Joshua James Hatherley argues that, if physician-assisted suicide (PAS) is morally permissible for patients suffering from somatic illnesses, it should be permissible for psychiatric patients as well. He argues that psychiatric disorders do not necessarily impair decision-making ability, that they are not necessarily treatable and that legalising PAS for psychiatric patients would not diminish research and therapeutic interest in psychiatric treatments or impair their recovery through loss of hope. However, by erasing distinction between somatic and psychiatric (...) disorders on those grounds, he also erases distinction between healthy adults and patients (whether somatic or psychiatric) essentially implying that PAS should be available to all, for all reasons or, ultimately no reason. Furthermore, as psychiatric patients are much more likely to be a source of usable organs for transplantation, their broad inclusion would strengthen the link between PAS/euthanasia and organ donation, potentially undermining both as well as diminishing already declining general trust in medical authorities and professionals and public health authorities and activists. (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)

Volume 24, Issue 7-8, November - December 2019, Page 876-880.

Slippery slope arguments have been important in the euthanasia debate for at least half a century. In 1957 the Cambridge legal scholar Glanville Williams wrote a controversial book, The Sanctity of Life and the Criminal Law, in which he presented the decriminalizing of euthanasia as a modern liberal proposal taking its rightful place alongside proposals to decriminalize contraception, sterilization, abortion, and attempted suicide (all of which the book also advocated).1 Opposition to these reforms was in turn presented as exclusively (...) religious and particularly Roman Catholic. Thus Williams asserted that "euthanasia can be condemned only according to religious opinion" (1957, p. 312).The following year, in .. (shrink)