A subjective proposition is a statement about reality whose truth is dependent on the perception of an individual. For example, "Painting X is beautiful." The truth of this statement depends on the person viewing X since the meaning of "beautiful" is a complex degree of aesthetic delight in a viewer. In other words, saying "X is beautiful" is similar to saying, "X causes a specific kind of visual stimulation." This statement has no meaning apart from an observer who can view X. Therefore, X is subjectively beautiful whether every possible viewer would see X as beautiful or only a few people. More generally, a subjective proposition can be defined as a statement in the form of A causes B in perceiver C. The truth of this statement depends on the C, and so the truth of "A causes B" is subject to the nature of C. Therefore, without the existence of C, A causes B is meaningless (neither true nor false). The idea of a painting being beautiful or of some candy tasting sweet is meaningless without perceivers of the painting or of the candy.

In contrast, an objective proposition is a statement about reality whose truth is independent of the perception of an individual. In other words, A has attributes B regardless of perceiver C. For example, "The earth is a sphere." The meaning of these words has nothing to do with how a perceiver is affected. Therefore, the earth actually is (or is not) a sphere whether any perceivers exist at all. We should recognize that the idea that the earth is flat does cause a belief (ranging from assertion to agnostic to negation) in the perceiver. As a result, the idea of A having attributes B, causes C in perceiver D. However, the truth of A having attributes B is independent of C or D.

The question we want to answer is "are moral ideas subjective ideas or objective?" A moral idea is any statement of what should be the case. These statements should be contrasted with statements that describe what might be the case and those that describe what actually is the case. An example of a moral idea is person X should tell the truth in situation S. Is the meaning of "should" a sensation in a perceiver? If so, then saying, "X should tell the truth in situation S" is equivalent to saying, "The idea of X telling the truth in situation S causes feeling F in perceiver P." By contrast, if the meaning of should is a real attribute of the situation it is applied to, then saying, "X should tell the truth in situation S" is equivalent to saying, "Person X telling the truth in situation S is a case with the attribute of ‘should be.’" Or to be more precise, "If situation S, then person X tells the truth" has the attribute of being right. Remember, what should be the case isn’t the same as what actually is the case; so it might be true that Person X won’t tell the truth in situation X even though it is still right for X to tell the truth in situation S. In other words, "If situation S, then Person X tells the truth" could have the attributes of being both right and incorrect if moral ideas are objective. If morals are subjective, then the above statement is neither right nor wrong. It is simply without real meaning. In general, statements of moral objectivity are in the form, "’Given S, X does Y’ has attribute A", and statements of moral subjectivity are in the form, "’Given S, X does Y’ causes A in perceiver B." Are statements of moral objectivity meaningful?

Now that the question has been defined, I think the answer becomes easily evident. People not only have certain feelings in response to moral ideas, they also think that their feelings apply to those ideas, that they are attributing to those ideas an intrinsic characteristic. For example, someone might say "she has no right to foist her moral ideas on him." It isn’t merely the case that the idea of someone foisting moral ideas on another person stimulates particular feelings in the perceiver. The perceiver also considers the idea of someone foisting moral ideas on another to have the characteristic of being wrong. To be sure, what if another person came along and said, "foisting moral ideas on others is right"? Wouldn’t the first person be inclined to disagree, and perhaps even try to explain to the second person why he’s incorrect? If the assessment of all moral ideas is similar to the taste of various foods, then no one’s assessment could be more accurate than anyone else’s. Accuracy would be a meaningless term since what tastes good for one person may not be what tastes good for another. No one would even consider trying to convince a person who didn’t like a certain candy that that candy has an intrinsic quality of tasting good. This is because the very meaning of the word "taste" includes the perception of a taster. But people are always trying to convince others that their own perception of what ought to be is somehow more accurate. This is a major clue that "ought" does not include in its meaning the perception of a perceiver, but is itself an intrinsic attribute of moral ideas.

Someone might complain that cultures stress different values and so what is right in one culture may not be right in a different culture. This idea of moral relativism does not defeat moral objectivism and is in fact irrelevant. For saying action A in culture C1 for person P is wrong, while action A in culture C2 for person P is right is not a contradiction of objective moral ideas since these sentences still fit the form "Given S, X does Y". It may even be that what is right for one person is wrong for another as a result of the personality or belief differences in those people. Even so, it can still be the case that "should be" is a real attribute of the moral idea that "Given S, X does Y." Moral objectivism involving moral relativism is still different than moral subjectivism. For moral subjectivism won’t allow "should be" to be applied to "Given S, X does Y". It only allows that a perceiver of the idea, "Given S, X does Y" will have experience E. Someone might argue that experience E includes the sensation that "The idea ’given S, X does Y’ has the attribute of ‘ought to be.’" But if that is the case, then why not believe what our sensation is telling us, namely, that "ought to be" really applies to the idea "Given S, X does Y"?

An ironic problem for those who expound moral subjectivism is as follows: They think no moral opinions are more accurate than any other (just as no one’s taste of candy can be considered more accurate). As a result, it seems "wrong" to them that anyone would try to prove that their moral beliefs are superior. However, this sensation of "wrongness" can’t itself be superior to the moral idea that some beliefs are superior. In other words, it is irrational for a person to consider no moral ideas to be superior while also considering the moral idea that "people should recognize that no moral ideas are superior" to be a superior moral idea.

I think the final blow against moral subjectivity is its immediate epistemological impracticality. For me to deny that value can ever be an intrinsic property of ideas or of things is to deny the intrinsic value of such a denial. The denial stimulates experience E in me, but if experience E includes the sensation that the denial is actually worth me making in my situation, then surely worth is a real attribute of the idea of me making the denial of all worth. But of course such a denial is a contradiction, and therefore false.

Of course, I have only argued for the objectivity of morals and have not attempted to show that God is required to explain objective morals. Some propose that objective morals are simply basic or a description of the human nature and do not require a perfect Moral Ruler to account for them. I have serious doubts about how objective morals could exist without a perfect Moral Ruler, but that that's a discussion for another essay.