Читать книгу This Is Bioethics - Udo Schüklenk, Ruth F. Chadwick - Страница 39

3.47 Probably the most frequently used rhetorical tool in bioethics debates comes in the shape of slippery‐slope type arguments. Slippery‐slope type arguments come in various forms, but typically they are claims that something terrible would happen if we did a certain arguably desirable thing. A good example of this is: ‘If we introduce voluntary euthanasia for mentally competent terminally ill patients soon the mentally disabled will get murdered, just like the Nazis did.’ A conservative Canadian newspaper editorialized against euthanasia in that country, warning against ‘the slippery slope of assisted dying⁵⁵’.

3.48 Usually slippery‐slope type arguments are both emotionally appealing and invalid. There are two broad types of slippery‐slope arguments that you quite likely will come across in bioethical arguments. The first type of slippery slope argument is conceptual in nature. It is not as common as the causal slippery slope type argument in bioethics. Conceptual slippery slope arguments claim that the criteria that are proposed to govern new legislation or a new policy are sufficiently imprecise as to open the door to abusive practices. We will come across examples of this kind of slippery‐slope argument in Chapter 11 because conceptual slippery slope arguments appear frequently in discussions about end‐of‐life issues (Somerville 2014⁵⁶). The same holds true for causal slippery slope arguments (Somerville 2014⁵⁷). Causal slippery slope type arguments typically claim that if a given (possibly sound) policy were introduced, this would invariably trigger a chain of events leading to actions or outcomes that are unacceptable (Schüklenk 2011, 47–50).

3.49 Conceptual slippery‐slope arguments are difficult to evaluate as a matter of principle. If you were to legislate that only legally competent individuals suffering from a terminal illness would be allowed to request a medically assisted death, would that really lead to a slippery slope endangering the mentally incompetent or people with depression, say, because competence assessments are not as reliable as mathematical proof? It is difficult to address this argument, except by noting that we undertake competency assessments of individuals in a large number of situations on a daily basis. The proposition that we should never implement legislation unless the concepts are as clear as the laws of physics would in effect prevent us from legislating at all.

3.50 Causal slippery slope arguments are much clearer in nature. They stipulate that if you do X, Y will invariably follow. The claim here is, of course, empirical. The inevitability is what typically is in doubt. ‘For example, opponents of genetic testing and screening say that there is no way to control the slippery slope from therapeutic uses of these new techniques to eugenic ones’ (Schüklenk 2011, 47). There are several problems with these kinds of argument. For starters, we do not know whether the empirical slope that is claimed here does actually exist. Is the inevitability of what is claimed truly inevitable, let alone likely? Given the slippery slope concerns raised would it truly be beyond our capacity to regulate and legislate against such outcomes? Even if there were actions that could be described as eugenic, would they necessarily be unethical? One problem with this line of reasoning is that it often is rhetorical in nature. A label is attached to a particular outcome, typically in a question‐begging manner, with the obvious aim being to persuade us to reject both the outcome and the slippery slope event that led to it. This we are supposedly only able to achieve by rejecting a particular proposed policy or action. Last but not least, there is always the possibility that X occurred, and that Y occurred, and that we concur, on reflection, that Y is undesirable, yet Y turns out to be not actual causally related to X. An example for this scenario could be problematic cases in jurisdictions that have decriminalized assisted dying. Say there was a case where a homeless person was euthanized against their wishes. Opponents of assisted dying legislation would need to do more than point to this case to have a sound argument. They would have to show that there is a causal link between the decriminalization of assisted dying and the case in question. Typically causal slippery‐slope arguments fail on this count. Correlation is no proof of causation.

3.51 You should be on high alert whenever someone introduces slippery‐slope arguments in discussions not only of matters bioethics, but of any issue. Slippery slope arguments can be (logically) valid, but often they are not. Their weakness usually is lies in the lack of detail, all they do is to claim that something might happen, on the sketchiest of evidence, or lacking any evidence (Burgess 1993). You will find fine examples of slippery‐slope rhetoric in Chapter 8 in our discussion of reproductive human cloning as well as in Chapter 11 dealing with ethical issues at the end of life.