Henri Poincaré
Mathematics and Science: Last Essays

Chapter VIII

 


ETHICS AND SCIENCE

During the latter half of the nineteenth century, people often dreamed of formulating a scientific ethics. We were not content to sing the praises of the educational virtue of science, the advantages that the human soul derives for its own improvement from looking truth in the eye. We relied on science to place moral truths beyond all contestation as it has done for the theorems of mathematics and the laws stated by the physicists.

Religions can have a great power over believers; but not all persons are believers. Faith can be imposed on only a few; reason would impress itself upon all. We must address ourselves to reason; and I do not mean to that of the metaphysicist whose constructs are brilliant but ephemeral like soap bubbles which amuse us for an instant, then burst. Science alone builds firmly; it has constructed astronomy and physics; today it is constructing biology; by the same processes tomorrow it shall construct ethics. Its ordinances shall reign uncontested; no one shall be able to oppose them, and we shall no more think of rebelling against the moral law than we think today of rebelling against the theorem of the three perpendiculars or the law of gravitation.

On the other hand, there were people who associated with science every possible evil; who considered it as a school of immorality. It is not only that it assigns too much importance to matter, and that it deprives us of a sense of respect because we only respect that which we dare not look at. But shall not its conclusions be the negation of morality? As some famous author has said, it shall extinguish the lights of heaven, or at least, deprive them of all their mystery and reduce them to the state of common gas jets. It shall expose the stage effects of the Creator, who will thereby lose some of his prestige. It is not good to let children look into the wings; this could arouse in them doubts of the existence of the bogeyman. If we permit scientists to have their way, there shall soon be no morality.

What are we to think of the hopes of the one group and the fears of the other? I do not hesitate to reply: they are equally idle. There cannot be a scientific morality; but neither can there be immoral science. And the reason for this is simple; it is a-purely grammatical reason.

If the premises of a syllogism are both in the indicative, the conclusion will also be in the indicative. For the conclusion to have been stated in the imperative, at least one of the premises must itself have been in the imperative. But scientific principles and geometric postulates are and can be only in the indicative. Experimental truths are again in that same mood, and at the basis of the sciences, there is and there can be nothing else. That being given, the most subtle dialectician can juggle these principles as he may wish, combine them, and pile them up on one another. All that he will derive from this will be in the indicative. He will never obtain a proposition which will state: do this, or, do not do that; that is, proposition which affirms or which contradicts morality.

And therein is a difficulty which the moralists have encountered for a long time. They strive to prove the moral law; we must forgive them, since this is their trade. They wish to base ethics on something, as if it could be based on anything but itself. Science shows us that man can only debase himself by living in such or such a manner. And what if I care little about debasing myself and what if, what you call degradation, I call progress? Metaphysics obliges us to conform to the general law of being which it claims to have discovered. It is possible to reply: I prefer to obey my own particular law. I do not know what metaphysics will reply, but I can assure you that it will not have the last word.

Will religious ethics be more fortunate than science or metaphysics? Obey because God commands it, and because He is a master who can overcome all resistance. Is this a proof, and can we not hold that it is a fine thing to rise up against omnipotence and that, in the dual between Jupiter and Prometheus, it is Prometheus in torture who is the true victor? And also, to give in to force is not to obey; submission of the heart cannot be dictated.

Nor can we base ethics on the interests of society, on the notion of the fatherland, on altruism, since it would still need to be proved that one must of necessity sacrifice oneself to the city of which one is a part, or else to the happiness of others. And no logic, no science can provide us with this proof. What is more, the very morality of pure self-interest, that of egoism, would be power is since,. after all, we cannot be sure that it is best to be egoistic, and since there are people who are not.