As we just saw, there is no end to what can be used as a source in historical inquiry. This ensures an almost unlimited supply of source material. Still, we should not forget that for many questions that can be asked, the situation is not nearly as favorable as this general picture suggests. Sources are not distributed evenly across periods, areas, and subjects; nor are all sources equally useful. Not only can appearances be deceptive, but human-made sources can also be produced in order to deceive (interesting in itself, but then one has to recognize such instances first). There are no easy ways around this problem; thus, it is a mistake to consider, for instance, that inscriptions are always more reliable than literary texts. Every source has to be carefully scrutinized as to what it can actually contribute. A source is like a telescope, or a magnifying glass: without it we cannot see anything, but it sits between the observer and the observed and distorts whatever there is to see.
In the end, we are left with many questions to which none of the sources available provide any answer. Then one can sit and wait until new relevant sources will be found, or, more realistically, try to come up with some hypothetical answer: what seems to be at a given moment the best, most consistent explanation. Theory, model making and comparison by way of sources from other periods and places will usually play an important part in the formulation of any such hypothetical answer.
Someone eager to learn about the past will most of the time not immediately turn to the relevant sources, but will make use of modern literature that is based directly or indirectly on source material. If one is after some information concerning the early Roman Empire, one does not nowadays read the Roman historian Tacitus, but will seek this information in some work of reference or, if the need arises, in more specialist publications. This also holds good for the present-day historian, who, even when he or she might have been inspired by reading some sources, will not usually embark upon a study of all possibly relevant sources, but will first read modern scholarly works in order to be better able to formulate questions, to get acquainted with a wider context, or possibly to build some model to guide further research. Of course, the subject selected and the kind of information wanted determine at what moment one will one turn from the modern literature to the sources: treading relatively unknown paths, one will be forced to turn to the sources fairly soon. However, serious scholarship almost always necessitates going back to the sources sooner or later. In dealing with antiquity, these will often be published sources, such as text editions or excavation reports. This does not mean that the ancient historian need only pick up the sources in order to get the required information. It might be possible to quickly falsify the work of some other historian, but usually the sources, whether published or not, have to be interpreted in a painstaking process. This implies that although every piece of historical scholarship ultimately depends on the sources available, the relationship between the sources on the one hand and the publications based on those sources is hardly ever simple and straightforward: the necessary act of interpretation always interferes.
World History
