Summary
One of the most controversial issues in the history of ethical theory has to do with the respective place that should be given to reason and to the feelings in the formation of moral judgments. Throughout the Enquiry, Hume has recognized that both reason and the feelings are necessarily involved in the development of the principles of morality. It has not, however, been made entirely clear just what he believes the function of each of these two factors to be, and it is for the purpose of clarifying this point that he has added this appendix to the earlier work.
Because so much has been said in the various sections of the Enquiry concerning the feelings of approval for that which is useful and agreeable to ourselves and to others as the essential basis for morality, he now gives special attention to the subject of reason and the function which it performs in connection with moral sentiments. To make his position entirely clear, he finds it necessary to indicate both what it is that reason is capable of doing and what it is incapable of doing. This will not only throw light on the nature of the rational element that is involved in moral thinking, but it will enable one to avoid those errors which attribute to reason a function which properly belongs to the feelings.
In the first place, it requires no argument at all to establish the fact that reason is an indispensable tool for finding out what actions are the ones most likely to be of the greatest use in meetings the needs of a human society. This information will need to be based on past experiences, and obviously reason, or correct thinking, will be involved in drawing inferences with reference to the meaning of these past events and the likelihood of similar occurrences taking place in the future.
Calculations of this kind are not always an easy or simple process. Complications arise because what is of immediate benefit to one person or one group of persons may be detrimental to their interests in the future. Again, it is not at all uncommon for situations to develop where benefits to one group are at the same time decidedly injurious to others. Furthermore, because conditions are constantly changing, what was beneficial under one set of circumstances may be detrimental under the changed conditions. Reason must take into account all of these factors and determine with as much accuracy as is possible those actions which under the new and emerging conditions will be most useful in meeting human needs.
Although reason is essential for the purpose of supplying the necessary information about what is useful and agreeable, it is not sufficient to produce either blame or approbation. Reason may tell us what is an adequate means toward a certain end, but it cannot tell us whether a particular end is good or bad. Only feeling or sentiment has the power to do that. So long as we are indifferent toward an end or goal, we will be indifferent toward the means which will produce it. Sentiment is necessary for moral decisions and this sentiment is none other than a feeling of approval for that which promotes the happiness of humanity and a resentment of that which produces misery in place of happiness. In support of this thesis, Hume calls attention to five important considerations.
The first one is the fact that reason is competent to judge only two things: matters of fact and the relations which exist between things. Neither of these is sufficient to cause approval or disapproval of an action. The fact that a theft or a murder has been committed does not in itself constitute any grounds for a favorable or an unfavorable attitude toward what has occurred. As a mere statement of fact, it is indifferent so far as any moral consideration is concerned.
What makes an act a crime is not something that exists apart from the minds of the persons who are thinking about it. That which is condemned or approved is not simply an awareness of the facts. Neither is it a matter of knowledge concerning the relationship of the facts to one another. It is only when the mental action or quality gives to the spectator a sentiment of approbation that we call it a virtuous act, or when it arouses a sentiment of resentment that we call it a vicious one.
The second consideration has to do with the difference between mistakes concerning matters of fact and mistakes with reference to morals. To know that a certain geometrical figure is a triangle involves an awareness of the relationship of the parts to one another. Here we can know at once all of the relationships that are relevant to the problem. This is not the case when we are dealing with morals.
When, for example, a person has been killed, we do not know at once all of the relationships that are involved. Consequently, we cannot say whether the act was a criminal one until we find out all the relevant circumstances under which the act took place. We need to know whether the killing was accidental or intentional, whether there was a sufficient justification if the act was intentional, and a number of other conditions which might have a direct bearing on the nature of the act. It is not until after all of these circumstances are known that the act can be praised or blamed, and even then it is the feelings, or the heart, that makes the decision rather than the intellect.
The third point calls attention to the similarities between an awareness of natural beauty and one of moral beauty. In both instances, some account is taken of the relationship of parts to the whole. Natural beauty depends very largely on such items as proportion, position, and the relation of parts to one another. It would be quite absurd to maintain that the beauty of an object consists purely in a knowledge of the particular facts that are involved. It is only when an appreciation or response is felt on the part of the observer that it is said to be beautiful. A similar situation exists with reference to moral beauty. Whether a particular act is to be regarded as a vice or a virtue is not determined by a mere awareness of the facts but by the presence of a feeling or sentiment which because of the structure of human nature causes us to be pleased or pained by what has taken place.
The fourth point is based on a comparison of the relationships involved in inanimate nature with the ones experienced in a moral situation. We do not censure a tree or a plant for destroying its parent in order to make possible its own growth and development, but we do regard it as a criminal act for a human being to kill his or her parents for any selfish purpose. The fact that the relationship between offspring and parents is the same in both cases is a clear indication that what is moral or immoral about an act is not simply a matter of relationship, knowledge of which is obtained through the reasoning process.
The fifth consideration is the fact that the ultimate ends of human action can never be accounted for by reason. If we want to acquire health, the reason can supply information concerning the proper means for obtaining it, but reason cannot prescribe the ends for which the means shall be used. Many of the things which we normally desire are only the means for obtaining something else, and these in turn are often the means for some more ultimate goal.
Means, however, must always be means for something, and somewhere along the line we must come to that which is no longer a means for something else but an end in itself. This is what we usually have in mind when we speak of the final ends, or goals, of human life. It is important to note in this connection that these final ends are necessarily the objects of feelings and desires. Unless we want to possess them, there is nothing in the nature of reason that tells us we ought to have them.
