A member of the studio audience has, in effect, asked me to present the fundamental theory of value on which my writings and moral judgments are built.
So, do you think that we "ought to do" anything?
I want to start by saying that I went to college for 12 years studying fundamental theories of value (moral philosophy). Consequently, a great deal of work has gone into this answer. Though hard work is no guarantee of good results.
The answer is: It depends on exactly what you mean by "ought to do".
Do I believe that certain actions contain an intrinsic "ought-to-do-ness" (or "ought-not-to-do-ness") built into them by a god or nature?
The answeris: No.
There is nothing that we ought to do in this sense. No action has such a property.
However, there is another type of "ought" entity that is very real - the hypothetical ought ot "hypothetical imperative".
It works like this:
If you want to avoid the agony of severe pain, then you ought to keep your body out of hot fires.
For most of us, we want to avoid the pain of being burned, so we have reason to act (we ought to act) in ways that will avoid a state in which our bodies are exposed to hot flames. Avoiding hot flames is something each of us ought to do.
This ought only applies to those who have an aversion to the pains (or who have reason to avoid damage to body structions - prevent infections, maintain the use of limbs and sense organs, prevent disfigurement) that would be caused by burns. Certainly, it does not follow that a person with none of these interests has a reason to avoid hot flames.
For the rest of it, it further follows that we have reason to install smoke detectors in their homes and test them regularly. We ought to make sure that our houses are wired in such a way that the wiring will not spark a fire. We ought not to smoke when we might fall asleep. (We ought not to smoke for other reasons as well.)
It is quite possible (and, in fact, very common) that an agent might have a reason to avoid hot flames and, at the same time, a stronger reason to act that requires exposure to hot flames. A parent may have a child caught in a burning house. The aversion to having the child suffer harm may be stronger than the aversion to the pain of burns. These aversions would motivate the parent to find a way to save the child without getting burned. However, where there is no option, the "ought to avoid hot fires" gets overridden by "ought to run into the burning house and rescue the child".
These aversions to the pain of severe burns and desires to protect children from harm are very real. They are as real as plants and planets. We see them working all around us every time we see other people in action - or other intentional agents. Consequently, the "oughts" that spring from them are very real.
It is also the case that, while biology gives us a some strong interests, our interests are not fixed by nature. Some of them are learned by our interactions with the external world. We learn to like or dislike certain things.
I mentioned that the interest in avoiding the pain of burns implies an interest in making sure that the house is wired correctly. This, in turn, implies a set of standards for evaluating electricians. A good electrician is one that has those qualities that would tend to fulfill the desires people seek to have fulfilled when they call an electrician. For example, a good electrician will wire a house in such a way that would tend to avoid sparking a fire. This would combine with other qualities such as working efficiently, inexpensively, and and communicating well with the employer. These standards are not arbitrary - they are standards whereby a good electrician tends to do a better job fulfilling the desires of traditional electrician-seekers than a poor electrician.
This makes it possible for a community to speak intelligibly and intelligently about the qualities of different electricians (or smoke detectors). These are very real standards - and they are substantially independent of what any particular person may want or believe. It allows people to make statements about the quality of electricians and smoke detectors that are substantially true (or false).
In the same way that there are standards for good electricians and good smoke detectors, there are standards for good neighbors. Following the same formula, a good neighbor has those qualities that people generally have reason to want to find in a neighbor. A poor neighbor lacks those qualities.
A good neighbor is averse to wantonly doing harm or to disturbing others with noises that would thwart the interests others have in sleep or a restful time in the back yard. She is honest and kind. She watches over our property when we are away and watches over our children as they play. She will take action to secure our rescue if she looks out her window and discovers that you have gotten ourselves pinned underneath your car. To the degree that we are good neighbors we do the same for them.
From here we get standards such as "Neighbors ought not to lie, or to take without consent, or to commit murder." Good neighbors have aversions to these kinds of things.
The qualities that people generally have reason to seek in a neighbor is not up to personal whim. There is a fact of the matter as to which qualities tend to be pleasing or useful to others.
As I said above, some of these qualities are fixed by nature. Thus, it makes no sense to praise or condemn neighbors based on these qualities. On the other hand, some qualities are acquired based on experience. By controlling the experiences our neighbors have (particularly young neighbors or family members) we can influence the qualities that they acquire.
The tools that we have for this include praise and condemnation. We have reason to praise those qualities we have reason to promote - honesty, kindness, helpfulness. We have reason to condemn those qualities that we have reason to inhibit in our neighbors - such as an interest in wanton violence or a level of greed that makes one a threat to others.
In other words, we create an institution called "morality."
The standards of morality are not a matter of personal opinion. There is a fact of the matter regarding the qualities that people generally have reason to promote or inhibit. There is a matter of fact as to what it makes sense for people generally to praise or condemn.
This answers the second question:
I do not understand how one could choose a logical desire under those conditions.
There are logical desires in terms of desires that people generally have reason to promote or inhibit. There are no logical desires in terms of desires that have an intrinsic "ought-to-have-ness" or "ought-not-to-haveness". The first type of desire fully accounts for our moral institutions.