The operations which must necessarily be performed in order to pass from the inspection of documents to the knowledge of the facts and evolutions of the past are very numerous. Hence the necessity of the division and organisation of labour in history. It is requisite, on the one hand, that those specialists who occupy themselves with the search for documents, their restoration and preliminary classification, should co-ordinate their efforts, in order that the preparatory work of critical scholarship may be finished as soon as possible, under the best conditions as to accuracy and economy of labour. On the other hand, authors of partial syntheses (monographs) designed to serve as materials for more comprehensive syntheses ought to agree among themselves to work on a common method, in order that the results of each may be used by the others without preliminary investigations. Lastly, workers of experience should be found to renounce personal research and devote their whole time to the study of these partial syntheses, in order to combine them scientifically in comprehensive works of historical construction. And if the result of these labours were to bring out clear and certain conclusions as to the nature and the causes of social evolution, a truly scientific "philosophy of history" would have been created, which historians might acknowledge as legitimately crowning historical science. Conceivably a day may come when, thanks to the organisation of labour, all existing documents will have been discovered, emended, arranged, and all the facts established of which the traces have not been destroyed. When that day comes, history will be established, but it will not be fixed: it will continue to be gradually modified in proportion as the direct study of existing societies becomes more scientific and permits a better understanding of social phenomena and their evolution; for the new ideas which will doubtless be acquired on the nature, the causes, and the relative importance of social facts will continue to transform the ideas which will be formed of the societies and events of the past.[231] II. It is an obsolete illusion to suppose that history supplies information of practical utility in the conduct of life (_Historia magistra vitæ_), lessons directly profitable to individuals and peoples; the conditions under which human actions are performed are rarely sufficiently similar at two different moments for the "lessons of history" to be directly applicable. But it is an error to say, by way of reaction, that "the distinguishing feature of history is to be good for nothing."[232] It has an indirect utility.