that, for example, “Seius is here and now committing theft, Titius is committing highway robbery,” so no prudent man would dare deny that, when we assert “Seius is committing theft, Titius is committing highway robbery,” a demonstration can be given that these same persons are sinning against the Law of Nature;5 at all events, that one would be any less certain about this point than about that which is inculcated ad nauseam in the bodies of doctrine which by universal consent rejoice in the certainty of sciences, to wit, that “man is risible, because he is rational,” and that “a sparrow is one, true, and good, because it is an entity.”
All this was set forth not long since in a special treatise6 in the most clear and reliable manner by that illustrious man, Herr Erhard Weigel, Professor of Mathematics in the University of Jena, a respected friend of mine. He it was who first exhorted me to attempt something in this field, and his genius has supplied me with a most helpful torch in matters not a few. This task, furthermore, I have undertaken with the greater zeal, because also by a special inclination I felt disposed to studies of that kind, and because it seemed to be worth making the effort to prove that what is handed down on this matter does by no means all rest upon vacillating opinions, but flows clearly enough from fixed and first principles.
And now, as to the method of this book, reason herself, indeed, makes it sufficiently clear that a man who is about to set forth some discipline must at the outset explain precisely what is meant by the subject-matter which he is about to treat; then he must seek for fixed principles from which necessarily true declarations concerning these matters may be deduced. Hence, any doctrine ought to be complete in three parts, the first of which comprehends the Definitions, the second, the Principles, and the third, the Propositions or Conclusions derived from the principles; to these, if it appear necessary, a fourth is to be added, into which may be gathered those topics in which certainty does not clearly appear.7 For all that is commonly said about the difference between the synthetic and the analytic method is nonsense.8 However, it has seemed best to us not to assign a special book to the Propositions, but to subjoin each proposition forthwith to the definitions or the principles on which it primarily depended; for there is a certain aridity which seems to deform the body of doctrine in question if it be set forth divided up into minute parts in the fashion of the mathematical sciences.
One other thing should be noted here. We have drawn much <xxx> from that marvellous work, De jure belli ac pacis, by the incomparable Hugo Grotius. Although appearing to treat merely a part of universal jurisprudence, he has, nevertheless, touched upon most of its parts in such wise that scarcely anything can be written in this field without his name appearing either as authority or as witness.9 No small debt likewise do we owe to Thomas Hobbes, whose basic assumption in his book, De cive, although it savours somewhat of the profane, is nevertheless for the most part extremely acute and sound.10 These two authors we have preferred to cite here once for all, as it were, and have refrained from mentioning them in the body of our work whenever their opinion is followed, because, aside from the tedium of frequent citation, we have followed rather their arguments than their authority [autoritatem]. For whenever the zeal for truth has compelled us to disagree with them and others, we have withheld their names, so that we should not appear to be eager to win a petty glory for ourselves by plucking at the blemishes of great men. And we have always regarded it as foolish, when you know yourself to be a man by no means free from errors, to incite others by harshness of criticism to subject you to the same treatment. We feel the greater confidence that this modesty on our part will meet with favour among the prudent, seeing that it has too frequently happened among those who have professed the study of the humanities, that they have inhumanely attacked others not without words of contumely. <xxxi>
INDEX OF DEFINITIONS,
AXIOMS, AND OBSERVATIONS1
By the object of moral actions is meant all that with which they deal
A moral person is a person considered under that status which he has in communal life
A moral thing is a thing regarded in respect of its pertinence to persons
