In “Faith and Force,” Rand is not so nice to Kant:

What Kant propounded was full, total, abject selflessness: he held that an action is moral only if you perform it out of a sense of duty and derive no benefit from it of any kind, neither material nor spiritual; if you derive any benefit, your action is not moral any longer.  This is the ultimate form of demanding that man turn himself into a “shmoo” — the mystic little animal of the Li’l Abner comic strip, that went around seeking to be eaten by somebody.

How could Rand think this after reading Kant? Kant–who thinks you have only limited duties of altruism toward others? Kant–who advises us not to make ourselves into worms lest we be trodden upon? 

My guess is that Rand misunderstands the insensible man example from the Groundwork. The grief-ridden insensible man is emotionally unmoved by others’ suffering. Still, he acts beneficently towards them simply from duty. In this case, Kant tells us, his action clearly has moral worth. It seems that he has good character, for to have good character, Kant says, is to act from duty, not merely from inclination. (See G 4:398-99)

I think Rand probably read this but misunderstood it. My guess is she reads it as Kant saying A) that only a good will, the strength of will to do what’s right, is good, and B) that your actions have moral worth only if you act solely out of a sense of duty, taking no pleasure in what you’re doing, and only if you have no selfish reason to do it.

Against A: Kant’s point here is the only the good will is unqualifiedly good. He says that any thing that is normally good can in some cases be bad. So, for instance, the pleasure of hugging your child is good, but the pleasure of sadistic torture is bad. Courage is usually good, but a Nazi soldier’s courage isn’t. However, Kant thinks, a good will is unconditionally good. Now, he might be wrong about this, but it’s at least not what Rand accuses him of thinking.

Against B: Kant not only doesn’t say this, but can’t–it’s incompatible with the rest of his moral philosophy. There is a common confusion about this insensible man passage, in which people believe Kant asserts one has moral worth only if one has to fight opposing inclinations or one lacks the inclination to do whats right. This is incorrect.

First, the passages indicated are meant to describe a case where the motivation for right action is clear. Kant holds that our motivation is usually opaque to us; we aren’t very good at knowing what motivates us. In the case of the insensible man, since he lacks any inclination to do what’s right, we know for sure that he’s doing it out of duty. So, Kant’s point is that this is a case where we know the good will is sufficient to motivate him.

Second, here’s why the view Rand attributes to him is inconsistent with the rest of Kant’s views. Kant believes 1) you always have the freedom to do what’s right and to act in ways that have moral worth, but 2) you do not have complete freedom to control your emotions and inclinations. So, Kant can’t say that your actions only have moral worth if you lack any inclination to do them. After all, according to him, it’s in part luck whether you have various inclinations, but it’s not luck whether you act in ways that have moral worth. Not only does Kant fail to explicitly endorse the view Rand attributes to him, it’s incompatible with his moral theory and his moral psychology.

Note, that Kant distinguishes between 1) the rightness and wrongness of your actions, and 2) the moral worth of your action. But “moral worth of your action” means, roughly, the moral quality of your motives. So, for instance, suppose it’s right for me not to kill you. Suppose, in case A, I don’t kill you because I recognize you have rights. In case B, I don’t kill you because I just happen not to feel like it, but I would kill you if I did. In A, Kant says my action was right and has moral worth; in B, it’s right but lacks moral worth. Seems legit to me.

Now, for Kant, can your actions have moral worth even if you benefit from doing them? Yes, indeed. Kant thinks that your desire to do what’s right has to be strong enough to motivate you to do the right action, but it’s fine to have other reasons or motives to do it. I feed my kids 1) because it’s right, 2) because I love them, and 3) because I want to avoid punishment. On Kant’s view, if the motive toward duty is sufficient to motivate me here–if I were to continue feeding them even if I stopped loving them and could get away with neglect–then my action is not only right, but has moral worth.

Why does Kant rejects the idea that you have a duty to promote your own happiness? As far as I can tell, it’s that he believes it makes sense to say an agent has a duty to X only if X is the kind of thing the agent isn’t already automatically going to aim to do. (IIRC, Kant says “angels” would lack duties because they are automatically aim to do what’s right.) Kant believes that people automatically pursue their happiness, so there’s no reason to posit a duty to pursue it. (He does, however, thinks there are duties of self-respect.)

It’s too bad Rand had it out for Kant. Her views probably come closest to Kant’s than to any other major philosopher, perhaps even more than Aristotle. But I’ll leave that shocking claim undefended, because talking about Rand doesn’t pay my bills, and it’s too much work to do for fun.