Introduction to the study of history

by Charles Victor Langlois; Charles Seignobos

There are two ways of employing reasoning, one negative, the other positive; we shall examine them separately.

II. The negative mode of reasoning, called also the "argument from silence," is based on the absence of indications with regard to a fact.[200] From the circumstance of the fact not being mentioned in any document it is inferred that there was no such fact; the argument is applied to all kinds of subjects, usages of every description, evolutions, events. It rests on a feeling which in ordinary life is expressed by saying: "If it were true, we should have heard of it;" it implies a general proposition which may be formulated thus: "If an alleged event really had occurred, there would be some document in existence in which it would be referred to."

In order that such reasoning should be justified it would be necessary that every fact should have been observed and recorded in writing, and that all the records should have been preserved. Now, the greater part of the documents which have been written have been lost, and the greater part of the events which happen are not recorded in writing. In the majority of cases the argument would be invalid. It must therefore be restricted to the cases where the conditions implied in it have been fulfilled.

(1) It is necessary not only that there should be now no documents in existence which mention the fact in question, but that there should never have been any. If the documents are lost we can conclude nothing. The argument from silence ought, therefore, to be employed the more rarely the greater the number of documents that have been lost; it is of much less use in ancient history than in dealing with the nineteenth century. Some, desiring to free themselves from this restriction, are tempted to assume that the lost documents contained nothing interesting; if they were lost, say they, the reason was that they were not worth preserving. But the truth is, every manuscript is at the mercy of the least accident; its preservation or destruction is a matter of pure chance.

(2) The fact must have been of such a kind that it could not fail to be observed and recorded. Because a fact has not been recorded it does not follow that it has not been observed. Any one who is concerned in an organisation for the collection of a particular species of facts knows how much commoner those facts are than people think, and how many cases pass unnoticed or without leaving any written trace. It is so with earthquakes, cases of hydrophobia, whales stranded on the shore. Besides, many facts, even those which are well known to those who are contemporary with them, are not recorded, because the official authorities prevent their publication; this is what happens to the secret acts of governments and the complaints of the lower classes. This silence, which proves nothing, greatly impresses unreflecting historians; it is the origin of the widespread sophism of the "good old times." No document relates any abuse of power by officials or any complaints made by peasants; therefore, everything was regular and nobody was suffering. Before we argue from silence we should ask: Might not this fact have failed to be recorded in any of the documents we possess? That which is conclusive is not the absence of any document on a given fact, but silence as to the fact in a document in which it would naturally be mentioned.

The negative argument is thus limited to a few clearly defined cases. (1) The author of the document in which the fact is not mentioned had the intention of systematically recording all the facts of the same class, and must have been acquainted with all of them. (Tacitus sought to enumerate the peoples of Germany; the Notitia dignitatum mentioned all the provinces of the Empire; the absence from these lists of a people or a province proves that it did not then exist.) (2) The fact, if it was such, must have affected the author's imagination so forcibly as necessarily to enter into his conceptions. (If there had been regular assemblies of the Frankish people, Gregory of Tours could not have conceived and described the life of the Frankish kings without mentioning them.)

III. The positive mode of reasoning begins with a fact established by the documents, and infers some other fact which the documents do not mention. It is an application of the fundamental principle of history, the analogy between present and past humanity. In the present we observe that the facts of humanity are connected together. Given one fact, another fact accompanies it, either because the first is the cause of the second, or because the second is the cause of the first, or because both are effects of a common cause. We assume that in the past similar facts were connected in a similar manner, and this assumption is corroborated by the direct study of the past in the documents. From a given fact, therefore, which we find in the past, we may infer the existence of the other facts which were connected with it.

This reasoning applies to facts of all kinds, usages, transformations, individual incidents. We may begin with any known fact and endeavour to infer unknown facts from it. Now the facts of humanity, having a common centre, man, are all connected together, not merely facts of the same class, but facts belonging to the most widely different classes. There are connections, not merely between the different facts relating to art, to religion, to manners, to politics, but between the facts of 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.[201] 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.