religion on the one hand and the facts of art, of politics, and of manners on the other; thus from a fact of one species we may infer facts of all the other species.
To examine those connections between facts on which reasonings may be founded would mean tabulating all the known relations between the facts of humanity, that is, giving a full account of all the empirical laws of social life. Such a labour would provide matter for a whole book. Here we shall content ourselves with indicating the general rules governing this kind of reasoning, and the precautions to be taken against the most common errors.
The argument rests on two propositions: one is general, and is derived from experience of human affairs; the other is particular, and is derived from the documents. In practice, we begin with the particular proposition, the historical fact: Salamis bears a Phœnician name. We then look for a general proposition: the language of the name of a city is the language of the people which founded it. And we conclude: Salamis, bearing a Phœnician name, was founded by the Phœnicians.
In order that the conclusion may be certain, two conditions are necessary.
(1) The general proposition must be accurately true; the two facts which it declares to be connected must be connected in such a way that the one is never found without the other. If this condition were completely satisfied we should have a law, in the scientific sense of the word; but in dealing with the facts of humanity—apart from those physical conditions whose laws are established by the regular sciences—we can only work with empirical laws obtained by rough determinations of general facts which are