This blog entry is part 1 in a series on the moral argument. The entries in the series:
- The Moral Argument for God Part 1: Going from Morality’s Existence to God’s Existence
- The Moral Argument for God Part 2: Does Objective Morality Exist If God Does Not Exist?
- The Moral Argument for God Part 3: Does Objective Morality Exist?
- The Euthyphro Dilemma
- Epilogue: Awakening the Sensus Divinitatis
- If God does not exist, then objective morality does not exist.
- Objective morality does exist.
- Therefore, God exists.
Before presenting the argument from moral ontological simplicity I’ll define some key terms. By authority I mean being the source of some obligation. Moral properties (like moral wrongness) are objective in that they exist independently of human belief and perception of them. Morality is metaphysically necessary in the sense that its existence “couldn’t be otherwise.” If we let a possible world be a complete description of the way the world is or could be like, something like “kindness is a virtue” is metaphysically necessary in the sense that it holds in all possible worlds. Similarly, there is no possible world where “torturing infants just for fun” isn’t morally wrong. Moral ontology is the discipline that studies the foundations of morality (e.g. are moral properties like moral wrongness physical or nonphysical?). Thus an ontological explanation of morality is an explanation of how morality exists and what sort of reality it constitutes.
By “descriptive ought” I mean that type of ought that is nothing more than some purely descriptive state of affairs. That may sound strange, but one type of descriptive ought many of us are familiar with is the type found in hypothetical imperatives, which take the form of something sufficiently like, “If you want X, you ought do Y.” 18th century philosopher Immanuel Kant says the hypothetical imperative represents the “practical necessity of a possible action as means to something else.” An example of a hypothetical imperative is “If you want to do well in school, you ought to study” meaning something like, “As a matter of practical necessity, you need to study to do well in school.” Any type of “ought” that has no other properties besides purely descriptive ones is a descriptive ought.
By “prescriptive ought” I mean that type of ought that is not a descriptive ought, e.g. “You should not to torture infants just for fun.” The prescriptive ought is the type of ought used in morality; morality tells us whether we really ought to do something, and not merely whether certain actions are a good means to bring about some purely descriptive state of affairs. This is important because to get around the moral argument I’ve seen some atheists redefine morality so that it uses the descriptive ought.
The type of morality being referred to here involves the prescriptive ought, e.g. moral wrongness. An action is morally wrong for someone only if they ought not to do it. The property of moral wrongness is universalizable in that applies equally to all relevantly similar situations, and the property is supremely authoritative, overriding any other “ought” (e.g. legal rules). If we think of “moral rightness” as the property of following some moral obligation, we get the same thing as “moral wrongness” but in the opposite direction: an action is morally right for someone only if they ought not to do it etc.
Objective Moral Properties: Natural or Non-natural?
What it means for moral properties to be non-natural varies between writers, but we can borrow philosopher Robert Adam’s description that it means moral properties “cannot be stated entirely in the language of physics, chemistry, biology, and human or animal psychology.” Similarly, natural facts are facts that are entirely in the language of psychology and the natural sciences, e.g. “the dog suffered a painful injury” is a natural fact.
Either morality exists solely as part of the natural world (moral naturalism) or it exists to at least some degree as part of the non-natural realm (moral non-naturalism). One of these has to be true, because if morality exists neither as part of the natural realm nor as part of the non-natural realm, then it follows that morality does not exist as part of reality at all. If morality exists, some type of ontological explanation or other must be correct.
For the sort of morality we’re concerned with, moral non-naturalism appears to be true. Since physics, chemistry, etc. deal solely with purely descriptive states of affairs, natural properties and natural facts are purely descriptive states of affairs. As such, since moral oughtness is a prescriptive ought and not a descriptive ought, moral oughtness is non-natural and moral oughtness properties (like moral wrongness, where an action is morally wrong for someone only if they morally ought not to do it) are non-natural.
Another indication that moral properties are non-natural is their empirical undetectability and causal inertness. To illustrate what I mean by moral oughtness being empirically undetectable, imagine a moral nihilist (who disbelieves in moral oughtness) and a moral realist (who believes in moral oughtness) observe some jerk kicking a dog just for fun; the dog whimpers in pain and runs away. Both agree on all physiological and psychological facts, e.g. that the dog felt pain and suffered minor injury. The moral nihilist says, “I don’t think moral oughtness (like moral wrongness) is attached to that action.” The moral realist says, “I think moral oughtness (moral wrongness) is attached to that action.”
There is no empirical way to determine who is right here. Both views agree on all the same empirically observable facts, and moral oughtness being associated with certain physical facts (such as the dog’s injury) doesn’t explain any physical fact. Not only do we have zero empirical evidence for the existence of moral properties, we can’t have empirical evidence for moral properties since they’re empirically undetectable.
The dog kicker scenario also illustrates that moral oughtness is causally inert. Notice that whether moral oughtness is associated with natural facts (e.g. the dog’s pain and injury) or not, the physical conditions are the same in both cases, and so barring the supernatural, the presence or absence of moral oughtness makes no causal difference as to what those physical conditions will result in.
One version of the moral argument is that moral properties like moral wrongness are objective and non-natural, yet these nonphysical moral properties are attached to actions in the physical world (e.g. a man stealing a television having the nonphysical property of moral wrongness). An ontological explanation is needed for that, and one could argue that theism is the best ontological explanation. For example, moral wrongness being one and the same property as that which God forbids explains why moral wrongness is objective (God’s authority is supreme) and non-natural.
Another version of the moral argument is what I’ll call “the argument from moral ontological simplicity.” If one has trouble wrapping their head around “non-natural,” one can substitute the claim of objective moral properties being non-natural with objective moral properties being nonphysical, and that will be close enough for our purposes (as the dog-kicker scenario above illustrates, it does seem clear that objective moral properties are at least nonphysical).
The Argument from Moral Ontological Simplicity
It is a principle of rationality that all else held constant, the simplest explanation is the best and most probable one. Given that moral properties are nonphysical and thus that morality exists as part of the nonphysical realm to at least some degree, it is interesting to note what would happen if we posited just one nonphysical entity and tried to find the simplest explanation for it grounding objective moral values and duties.
What must this nonphysical entity be like if we were to obtain the simplest explanation for it grounding objective moral values and duties? As a nonphysical entity, it must transcend the physical world. This is not surprising, but the entity in question is also the foundation of objective moral duties, and as the source of moral obligation is must also have authority in the sense that it imposes moral duties and grounds the “oughtness” of those duties. Moreover, for morality to be objective and universally binding, the entity must impose moral duties with supreme and universally binding authority, because moral duties supersede any other duties that any (other?) person or culture might create for themselves. Next, the entity must exist in every possible world (and therefore have necessary existence) to ground morality in every possible world, because morality is metaphysically necessary. While multiple entities spread about in different possible worlds grounding morality is logically possible, if we’re looking for the simplest explanation it is preferable to posit just one grounding entity to explain morality’s metaphysical necessity. And finally, the entity must also be eternal, since at no time and in no circumstances can metaphysically necessary entities fail to exist. Thus if we posit just one nonphysical entity and search for the simplest explanation for that entity grounding objective morality, we end up with an eternal, transcendent, metaphysically necessary entity that imposes moral duties upon us with supreme and universally binding authority. That this sounds so suspiciously like theism seems awfully coincidental.
Does this prove God’s existence with absolute certainty? No, but that we can so simply and straightforwardly go from morality’s existence to a God-like entity is notable evidence for theism. Although the above argument doesn’t say that the morality-grounding entity has to be a personal being, the entity being personal does, I think, most intelligibly account for the entity imposing duties upon us and having authority over people. If the entity is a personal being, we end up with an eternal, transcendent, metaphysically necessary being who imposes moral duties upon us with supreme and universally binding authority. We thus end up with some type of personal supreme being.
Objective moral properties are non-natural (or at any rate, nonphysical). Where a possible world is a complete description of the way reality is or could have been like, morality is metaphysically necessary in that it exists in all possible worlds; it cannot fail to exist. If we posit just one non-natural/nonphysical thing as the foundation for morality and tried to find the simplest explanation for that entity grounding moral values and obligations, we end up with an eternal, transcendent, metaphysically necessary entity that imposes moral duties upon us with supreme and universally binding authority. This observation (and the claim that it rationally supports theism to at least some degree) is what I’ve called the argument from moral ontological simplicity.
The argument from moral ontological simplicity is interesting because we start from some basic aspects of objective morality and reason from there to a God-like entity in a very straightforward manner. While this argument does not prove theism in any rigorous sense, it makes God look like an excellent candidate for grounding objective morality, and I think the argument enhances theism’s plausibility to at least some degree. And once the argument is made, I do not think it becomes tenable for the atheist moral objectivist to say, “I don’t need to provide an alternate foundation for objective morality.” With a God-like entity being such a simple and straightforward ontological explanation, the atheist moral objectivist owes us an ontological alternative. If no better alternative exists, I think theism wins the game of inference to the best explanation in regards to grounding objective morality.
What about atheism? Can it come up with a better ontological explanation? In part 2 of the moral argument, my next blog entry, I’ll discuss what I believe to be the best atheist ontological explanation for objective morality. I’ll also explain why I think it’s inadequate.
 Section 2 of Immanuel Kant’s Groundwork of the Metaphysic of Morals (a.k.a. Fundamental Principles of the Metaphysic of Morals) in Thomas Kingsmill Abbott’s translation.
 Adams, Robert M. The Virtue of Faith (New York: Oxford University Press, 1987), p. 145.
Last major edit of this article: 2016-12-02-FR