I have mentioned this argument in passing before. However, I would like to bring it to the forefront for some proper attention. It is an refutation of the following argument:
The definition of morality is subjective. Whatever definition I accept, you can accept a different definition, and there is no objective argument that will decide the case between us. Therefore, morality is subjective.
It really is a bad argument.
Atheists pride themselves on being rational, and Theists condemn them for their inability to make sense of morality. Atheists who use this argument simply concede the Theists’ point.
I can prove that this form of argument is invalid by use of the logician’s tool, “Disproof by counter-example.” All I need to prove that this argument is invalid is to provide another argument, having exactly the same form, and true premises, but a different conclusion. If I can provide such a counter-example, I can prove that the form of the argument being used is not one where the conclusion follows from the premises.
So, here is my counterexample.
The definition of planet is subjective. In about three months, the International Astronomical Union will propose a definition of the word ‘planet.’ The definition has become an issue recently because we have found another object 2003 UB313 in space that about the same size as Pluto is much like Pluto. However, it has very much in common with a group of objects on the edge of the solar system called Kuiper Belt Objects. So, astronomers need to know whether to call this new object and Pluto planets, or Kuiper Belt Objects.
The question that Astronomers need to ask is: What is the definition of a planet?
What is relevant here is that the definition is subjective. Astronomers are very much aware of the fact that the definition of a planet is subjective. There is no experiment that they can perform, no objective test, that will tell them whether define the word ‘planet’ in a way that includes Pluto, or in a way that excludes Pluto. There is some talk of putting it up to a vote.
Yet, nobody draws the conclusion that, “Therefore, planetology (or astronomy generally) is subjective."
The claim that the subjectivity of language implies the subjectivity of a field of study is false. Just as you cannot infer subjective astronomy from its use of subjective definitions, you cannot infer subjective morality from its use of subjective definitions.
The argument simply does not work. People who pride themselves on reason either should quit using it, and should quit giving it any respect when they are in the company of others who use it. They should pipe up, “No, friend. That is a mistake. You cannot infer that a field of subject is subjective from the fact that it uses subjective definitions. All fields of study use subjective definitions. Yet, some fields of study clearly are not subjective.”
So, what’s going on when people use this argument?
Actually, they are starting with an assumption that the meaning of ‘morality’ is not subjective at all. They are starting with the assumption that “morality” has a fixed and determined meaning that everybody agrees on. However, they do not agree on what that term refers to. It is like having a common definition of ‘planet’ that everybody uses. However, they cannot agree on whether 2003 has the criteria that would qualify it as a planet.
More importantly, to make this analogous to what people say is true of morality, we have to imagine that it is the case that if Person 1 calls Pluto a planet, then Pluto has those qualities that would qualify it as a planet for Person 1. Also, if Person 2 says that Pluto is not a planet, then Pluto would lack those qualities that would qualify it as a planet for Person 2. Yet, Person 1 and Person 2 are using the same definition. Somehow, by Person 1 calling Pluto a planet, it acquires properties (for Person 1) and that when Person 2 says it is not a planet it lacks those same properties (for Person 2).
However, I need a subjectivist to make sense of how this is even possible. How do the properties of an object change according to what it is named? How is it the case that by calling something X, it automatically acquires the properties that would qualify it as an X, whereas denying that it is an X means that it lacks the qualities that would qualify it as an X. Can somebody make sense about how this is possible?
One of the things that subjectivists note is that we have different preferences. When it comes to eating chicken, I like dark meat, and my wife likes white meat. If we describe parts of a chicken according to whether it suits are taste, I would say that dark meat is better than white meat, while she says that white meat is better than dark meat. The taste of chicken would then be subjective, right?
In a sense, we can say that it is subjective. However, this subjectivity has nothing to do with definitions. My wife and I are not having a disagreement over the definition of ‘better’. We are using the same definition: “…appeals more to the tastes of the speaker.” Using this common, mutually agreed upon definition, dark meat is better than white meat to me, and white meat is better than dark meat to her.
Note: I would vigerously dispute any claim that morality is like tastes in food. However, even if it were -- even if we give moral subjectivism its strongest case -- there is still a very strong sense in which it would not make sense to say that morality is subjective.
First, this is NOT a dispute over definitions. Those who try to explain this as a dispute over definitions do not understand what is actually going on.
Second, this is also not ‘subjective’ in another sense.
To illustrate the other sense in which this is not subjective, I would like to invent a word, “tallme”. I will define “tallme” to mean “taller than the speaker.” Now, imagine two people, Aaron (who is 6’ tall) and Bruce (who is 5’ tall). They both know Chuck (who is 5’6” tall). Bruce says that Chuck is tallme. Aaron says that Chuck is not tallme.
The point that I want to make here is that both of them are telling the truth. Bruce’s claim that Chuck is tallme is as objective – as factual – as it would be if he were to claim that Bruce is 5’6” inches. In both cases, Bruce would be giving Chuck’s objective height in terms of a measurement that comes from comparing it to another object – a yardstick in one case, and Bruce’s height in the other.
Statements about something being “good” or “bad” in the sense of “appeals to the tastes of the speaker” are no less objective than statements about “tallme” or “not tallme” in the sense of “compared to the height of the speaker.”
Any claim that “good” or “bad” describes a different type of quality is also false. A claim that “good” or “bad” describes a different type of quality also helps theists to make the claim that atheists cannot make sense of value.
So, I would really like to ask my readers, when they debate the issue of whether morality is subjective or objective, that they at least quit using these faulty arguments, and encourage others to do the same. It does no good to help theists make the claim that atheists cannot speak sensibly about morality.