Hume's Guillotine Cuts Cleanly

One (still) cannot derive an Ought from an Is. Enjoy a philosophical detour relevant to modern reasoning in an era rife with fallacy.

One cannot derive an "ought" from an "is." This idea was famously articulated by Scottish philosopher David Hume in his magisterial A Treatise of Human Nature (1739). This distinction has been the subject of deep debate misunderstanding, particularly in metaethics and the philosophy of science.

Unlike other puzzling philosophical issues, this one strikes me as both correct and intuitive: Hume was right then, and he is right now. But there are a lot of people out there who have an interest in blurring these distinct proposition types. And, of course, it’s fashionable to deny OLDTHINK, particularly when new thinkers want to distinguish themselves as part of some new philosophical paradigm.

The primary claim is that normative conclusions—what one “ought” to do—cannot be deduced or induced from positive premises—what “is” the case. In other words, two distinct claims reflect two distinct domains: the mind-independent world as it is (facts) and what people think they wish the world to be or their affective evaluations of that state of affairs (values).

I don’t care if you’ve drowned yourself in postmodernism, are an acolyte of Ayn Rand, or are well-steeped in the works of Paul Feyerabend or Thomas Kuhn, Hume’s guillotine cuts cleanly and decisively between facts and values.

I suspect people go astray for one of four primary reasons:

1. Kuhn. After reading Thomas Kuhn, I’ve come to the conclusion that science is “value-laden,” which means values and facts are blurred.

2. Harris. I really want to believe science can show us the way to morality in a godless world—which means I must play handmaiden to scientism.

3. Rand. I am equivocating (perhaps unwittingly) on two subtly different meanings of the relevant words while appealing (again) to the “self-evident.”

4. Activists. I am an activist, so my wishes tend to spawn my lies. My activism obliges me to go all-in on my ‘oughts’ and deny the world’s unforgiving reality.

Let’s explore each in turn.

Kuhn

I am not going to argue that Thomas Kuhn disagrees with Hume. Instead, I will argue that people misuse Kuhn to argue that values can be derived from facts. One of Kuhn’s major insights was that science is value-laden. Our various approaches to science through the years subtly or not-so-subtly involve biases that can shape scientific paradigms.

1. Geocentric to Heliocentric Model of the Solar System

   • Geocentric Model. Earth is the center of the universe (Ptolemaic).

   • Heliocentric Model. The sun is the center of the solar system (Copernican).

2. Classical Physics to Relativity and Quantum Mechanics

   • Classical Physics. Newton’s laws of motion and gravity.

   • Relativity. Einstein’s theories, including special and general relativity.

   • Quantum. Describes physics on very small scales and introduces concepts like wave-particle duality.

3. Miasma Theory to Germ Theory of Disease

   • Miasma Theory. Diseases are caused by "bad air".

   • Germ Theory. Diseases are caused by microorganisms.

Kuhn's seminal work, The Structure of Scientific Revolutions (1962), challenges the notion that the progress of science is an objective, cumulative process. According to Kuhn, scientific development occurs through a succession of paradigm shifts. In this context, a paradigm is an accepted set of practices, techniques, and beliefs that compose a scientific discipline in any given era. Kuhn argued that paradigms are influenced by various factors, including social, cultural, and political values—as well as by scientists' own biases. As Covidian zombies like to assert:

Trust the Science.^TM

Paul Feyerabend was even more hardcore than Kuhn. Feyerabend's philosophy of science suggests the enterprise is inherently value-laden because there are no objective criteria to determine what should count as good science. Feyerabend also explored all the myriad ways in which science gets entangled with our values and highlighted the impact of power relationships on scientific practice—an insight that has become far more salient in the post-COVID era.

Again, though, just because Feyerabend thinks people blur facts and values doesn’t mean he also thinks claims such as I dislike chair c can be inferred from claims like Chair c exists with y properties. Similarly, Act x is wrong cannot be deduced from A committed act x against B.

Knowledge of c or x or its properties informs but doesn’t determine our valuations.

So yes, it should be obvious that science and epistemology can be value-laden. But the fact that biases or values inform or shape our ways of knowing doesn’t mean the nature of external reality magically determines objective moral truths.

Harris

In an essay bizarrely titled “Toward a Science of Morality,” which reflects his thinking in The Moral Landscape, Sam Harris attempts to dull Hume’s Guillotine:

While it is possible to say that one can't move from "is" to "ought," we should be honest about how we get to "is" in the first place. Scientific "is" statements rest on implicit "oughts" all the way down. When I say, "Water is two parts hydrogen and one part oxygen," I have uttered a quintessential statement of scientific fact. But what if someone doubts this statement? I can appeal to data from chemistry, describing the outcome of simple experiments. But in so doing, I implicitly appeal to the values of empiricism and logic.

Could this be Kuhn in a different garb? One can imagine sitting at a poker table with Harris, listening to him utter that last sentence with a poker face: “I implicitly appeal to the values of empiricism and logic.”

But we must call his bluff.

The is/ought distinction rests more on metaphysics than epistemology—that is, the nature of reality rather than our ways of knowing. While epistemic claims usually require metaphysical commitments, Hume’s point is that people play different language games with ISs and OUGHTs. One game is metaphysical, and the other is perhaps aspirational—e.g., how you wish someone were (future) or had been (past).

If I make an epistemic claim, I am making a certain kind of claim about how my thoughts and language about my thoughts stand in a certain kind of relation to the world. The world doesn’t care. As so-called “red-pilled” types are fond of saying:

Facts don’t care about your feelings.

But Harris doubles down on the weak hand:

What if my interlocutor doesn't share these values [empiricism and logic]? What can I say then? What evidence could prove that we should value evidence? What logic could demonstrate the importance of logic? As it turns out, these are the wrong questions. The right question is, why should we care what such a person thinks in the first place?

We can at least agree with Harris about the “right question,” particularly if we’re talking about the interlocutor’s metaepistemology—how we really know we know or how best to gain knowledge—instead of some question about brute reality.

In The Moral Landscape, Harris argues that we can derive values from facts—specifically, facts about the well-being of conscious creatures. According to Harris, questions about values are really questions about the well-being of conscious creatures, and since we can, in principle, have factual knowledge about well-being, science can determine human values!

The big problem with this idea is that questions about human well-being equivocate on the term “ought.” As we’ll see with Ayn Rand, Harris confuses instrumental rationality with morality.

Rand

In answer to those philosophers who claim that no relation can be established between ultimate ends or values and the facts of reality, let me stress that the fact that living entities exist and function necessitates the existence of values and of an ultimate value which for any given living entity is its own life. Thus the validation of value judgments is to be achieved by reference to the facts of reality. The fact that a living entity is, determines what it ought to do. So much for the issue of the relation between “is” and “ought.” -Ayn Rand, from “The Objectivist Ethics”

Consider the following example where someone might say:

1. Smoking is harmful to your health.

2. Therefore, you ought not to smoke.

Unless we’re worried about inviting God’s ire by messing with His creation, we have to interpret this claim as instrumental rationality, not morality. Instrumental rationality takes the form:

If you want x, then you should do y.

In other words, the speaker is not arguing it is morally wrong to smoke, but rather that if you want to be healthy more than you want to enjoy smoking, then you would be wise not to smoke.

Rand’s argument in the quotation above can be interpreted in two ways: either as instrumental rationality (which is not morality per se) or as saying something obvious that doesn’t contradict Hume. In the first interpretation, If you wish to live, then you should use your mind to survive. Hume would say that such a claim is not the same as You ought to use your mind to survive, but if you don’t, you’re immoral!

That latter interpretation would make Rand downright Kantian.

The Activists

Activists aren’t terribly philosophical. They are usually sad, Machiavellians, or sad Machiavellians. Sadly, they start from moralisms cum cognitive distortions and then make errant claims about so-called “facts,” or they make errant claims about the “facts” and then turn their moralisms up to 11.

As philosopher

Michael Huemer

writes:

[T]he status of ‘thought crime’ does not in general attach to beliefs that are so conclusively refuted that anyone who investigates carefully will reject them. Indeed, it is precisely the opposite. It is precisely because epistemic reasons do not suffice to convince everyone of your belief that you attempt to convince them through moral exhortation. When the plea “Believe P because the evidence demonstrates it!” fails, then we resort to “Believe P because it is immoral to doubt it!” Indeed, you might reasonably take someone’s resort to moral exhortation as pretty strong evidence that they have a weak case, and they know it.

Sadly, activists have infested the state, the media, the schools, the universities, the AI companies and contributed to the censorship-industrial complex.

The Chorus

Whenever you defend David Hume, you’re going to get pushback. I suspect this case is no different. Therefore, do your worst in the comments. I’m always willing to be persuaded.

But, remember, George Carlin makes the case better than anyone.