David Copp starts of with two principles of rationality and moral reasons. (Copp, David, "Normativity, Deliberation, and Queerness" in A World Without Values: Essays on John Mackie's Moral Error Theory, (Richard Joyce and Simon Kirchin, eds.), 2010.)
Right out of the gate, I am afraid, I am not going to like either of these two proposals.
Authoritative Reasons Proposal: Necessarily, if a person has a moral obligation to do something, then (a) there is a moral reason for her to do it, and (b) if she is fully rational and believes she is obligated to do it or that there is a moral reason for her to do it, she takes this obligation or reason appropriately into account in deciding what to do.This is false.
I will start with the proposition that rationality relates actions to the reasons (desires) that an agent has, while morality relates actions to the reasons (desires) that an agent morally should have. The desires that an agent morally should have are the desires that other people have reason to cause agents to have. To the degree that there is a gap between the reasons an agent has and the reasons an agent should have, there is a gap between what an agent rationally ought to do and what the agent morally ought to do.
So, if we go back to the original proposal, it is the case that if a person has a moral obligation to φ (if a person with good desires would φ), then there are moral reasons for her to do it.
Now, if this agent is fully rational, and even if she believes that she is obligated to φ (that a person with good desires would φ), she may not have a reason to φ if the reasons she has diverges from the reasons she should have.
In fact, the distance between the reasons an agent has and the reasons an agent should have - what it is rational for her to do and what it would be rational for a person with good desires to do - is the measure of moral evil.
Non-Instrumental Reasons: An agent S has a “non-instrumental reason” to φ just in case there is a reason for her to φ and the fact that this is so does not depend on S's having any particular desires, values, or interests, or on whether S's φing would be to her advantage.I will end up agreeing that there are non-instrumental reasons. These are desires that people have other than the agent. However, I am going to have trouble with the phrase that says that "agent S HAS a 'non-instrumental reason'". It is one thing to say that a non-instrumental reason exists. It is another to say that the agent has it.
When we look at the desires that other agents have, there is a difference between saying that those desires are reasons for her to φ, and saying that those desires are reasons for causing S to acquire a reason to φ. When I write about moral reasons, I am writing about the second of these two distinctions, not the first. This is captured in the distinction between the reasons that S has, and the reasons that S should have - the reasons that others have reason to cause her to have.
So, "there is a reason for her to φ" means that there is a desire that would be fulfilled by her φing. Such a desire would count as a reason to bring it about that S does φ. However, it does not count as a reason that S has to φ. It is possible that no such reason exists.
There are what we might call "non-instrumental reasons" that exist (desires that exist) that are independent of the desires, values, and interests that S has (unless S is the only person in the world). However, to say that S has a non-instrumental reason merely because other reasons exist is confusing at best. Instead, we can more clearly express this idea by saying, "There exists non-instrumental reasons for S to φ just in case there are reasons (desires) for her to φ that are not her own and, thus, do not depend on S's having any particular desire, value, or interest."
I want to note that Kopp himself rejects Proposal 1. That is to say that Kopp is not defending these proposals. He simply wants to discuss them. Specifically, he wants to argue that, if Proposal 1 is true, "that moral naturalism has nothing to fear from the proposal".