The Best Defense of Ethical Intuitionism
His intention is to defend ethical intuitionism (according to which some of our ethical knowledge is non-inferential) against an objection put forth by Nicholas Sturgeon. The thesis is this: irrespective of whether intuitionism takes non-inferential ethical knowledge to be a posteriori or a priori, intuitionism isn’t committed (as Sturgeon claims) to the existence of non-inferential knowledge in areas outside ethics in which its existence would be implausible (such as the past, the future, or the unobservable). These are the good news – but there is also bad news: even if ethical intuitionism is not committed to an implausible epistemology outside ethics, its versions (a priori and a posteriori ethical intuitionism) might be committed to an implausible epistemology within ethics.
I. So here it is, first, the standard argument for ethical intuitionism (a very clear and elegant one, in my opinion):
(S1) If we have any ethical knowledge, then that knowledge is either (a) non-inferential, or (b) based by reasonable inference on partly ethical premises, or (c) based by reasonable inference on entirely non-ethical premises
(S2) The Autonomy of Ethics: There is no reasonable inference (deductive or non-deductive) to any ethical conclusion from entirely non-ethical premises
(S3) Therefore, if we have any ethical knowledge, then that knowledge is either (a) non-inferential or (b) based by reasonable inference on at least partly ethical premises
(S4) Foundationalism: If we have any knowledge (e.g. ethical knowledge) that is inferential, then all such knowledge is ultimately based by reasonable inference on some knowledge that is non-inferential
(S5) Therefore, if we have any ethical knowledge, some of it is non-inferential
(S6) Ethical Non-Skepticism: We have some ethical knowledge
(S7) Therefore, some of our ethical knowledge is non-inferential
Since the above standard argument is valid, any critic of ethical intuitionism must reject S2 or S4
Note: foundationalism + autonomy of ethics ® a choice between intuitionism and skepticism [note that the argument can be generalized to any other topic, it is not specific to ethics]
II. Let’s see now Nicholas Sturgeon’s objection. He says that, given a certain plausible general rationale for the autonomy of ethics, intuitionism implies an implausible epistemology outside ethics, because of its commitment to foundationalism.
Sturgeon’s naturalistic “rationale” for the autonomy of ethics is this: our thought about the natural world is populated by areas that are autonomous with respect to the evidence we bring to bear on them [because assessment of evidence for theoretical conclusions are theory-dependent (the same explanation works for the autonomy of many areas of thought about the natural world]. Now the problem is that the naturalistic rationale for the autonomy of ethics comes with a high epistemological cost: it commits us to the autonomy of our thought about the past, the future and the unobservable; so the intuitionist must accept that we have non-inferential knowledge in these topics too. As a consequence, if ethical intuitionists accept the autonomy of ethics, then combining it with foundationalism commits them to an implausible overall epistemology. But to give up foundationalism is to give up ethical intuitionism.
III. Now take the following definitions:
a) a posteriori ethical intuitionism = the claim that if we have any non-inferential a posteriori knowledge, presumably some of it we have by perception.
b) a priori ethical intuitionism = the claim that some of our ethical knowledge must be non-inferential a priori knowledge.
Pekka Väyrynen shows that neither of the above versions of ethical intuitionism is committed to an implausible epistemology outside ethics. But they might be committed to an implausible epistemology within ethics. The arguments go like this:
a) in order to respond to the objection according to which all knowledge is inferential, a posteriori ethical intuitionism should hold that at least some experiences that correctly represent an ethical property as being instantiated are perceptions of that ethical property as being instantiated. Bu the problem is that establishing that we can perceive ethical properties as being instantiated is difficult. Still, if we could perceive ethical properties as being instantiated, then some ethical knowledge is non-inferential. If we can perceive ethical properties as being instantiated, it doesn’t follow that in the similar way perception gives us non-inferential knowledge about topics like the past, the future, or the unobservable. So the question remains whether the reply commits a posteriori intuitionism to an implausible epistemology within ethics. This depends crucially on whether we can perceive ethical properties as being instantiated.
b) a priori ethical intuitionism holds that a self-evident proposition is a truth any adequate understanding of which is such that (a) one has justification for believing the proposition in virtue of having that understanding of it and (b) if one believes the proposition on the basis of that understanding, then one knows it. Further, we can have non-inferential ethical knowledge on the basis of adequate understanding of certain propositions, without any further positive appeal to experience, even if experience, background beliefs, or inferences are capable of defeating our justification to believe those propositions. The only problem is whether there are self-evident ethical truths. If there are self-evident ethical truths, then one can accept both foundationalism and the autonomy of ethics without committing oneself to self-evident truths that could give us non-inferential knowledge in other areas. So the idea is that we need a reliable test for determining whether a proposition is self-evident. A priori intuitionists have yet to explain how an ethical proposition can be such that: a) an adequate understanding of it makes one to know that it is true but b) facts about its meaning or how that meaning is fixed don’t alone explain why its truth is knowable solely on the basis of an adequate understanding of it. So long as the existence of such synthetic self-evident ethical truths remain in doubt, our support for a priori intuitionism should be merely conditional.