According to DigoPaul, an auxiliary science is one that works as a support for another science so that it meets its goals and objectives. These are scientific disciplines that can complement a science in certain specific cases.
Although the term can refer to different sciences, the notion of auxiliary sciences is closely linked to history. That is why there are cases in which the mention of the auxiliary sciences makes explicit reference to the auxiliary sciences of history.
Archeology, law and etymology are some of the auxiliary sciences that provide documentation or sources of analysis to the historian. They are, in most cases, autonomous sciences that have their own methodologies, which means that the idea of auxiliary science is not exact and, for this reason, has fallen into disuse.
All this without forgetting that there are also other disciplines that can also be classified as auxiliary sciences of history. This would be the case, for example, of chronology, geography, iconography, heraldry, paleontology, geology, ethnography or papyrology.
However, all the aforementioned we can establish that they are grouped into two sets: the major auxiliary sciences, which are at the same level as history in terms of degree of development, and the minor auxiliary sciences, which are basically in charge of checking sources of information.
These auxiliary disciplines help the historian to analyze documents or relics and, in this way, know their historical origin, extract data and generate new information. The collaboration of specialists (for example, an archaeologist) is essential in many situations.
Several of the auxiliary sciences were developed from the study of questions that vary over time (such as chronology), while others arose from the comparison between different realities or factors (such as the history of art or the history of the law).
It should be noted that the written record of history is known as historiography. Therefore, historiography constitutes the epistemology of history.
However, there are also other disciplines, besides history, that also have their own auxiliary sciences. This would be the case, for example, of Criminal Law. In his case, legal medicine, criminalistics, criminal statistics or forensic psychiatry are considered disciplines supported by that.
The aforementioned legal medicine is the one in charge of determining the causes of death of a person while criminalistics is the one that, through certain procedures, carries out what is the collection of evidence and elements of various types that allow the author of the aforementioned death or criminal act to be clearly identified.
Criminal statistics, meanwhile, we can establish that it is that auxiliary science of Criminal Law whose object of work is the quantitative determination of crime rates in a given area. And finally, forensic psychiatry can establish that it is the discipline that undertakes the study of the behavior of the offender itself with the clear objective of determining whether there are certain ideas or elements in his head that prevent him from realizing the seriousness of the facts.