History is the lowest science of all. It is also the starting point of any of the higher sciences. History is the science of particular things. It is not a demonstrative science nor can it be one. Aristotle gave this as the reason that history was not a science at all, but his reason is flawed.
History is a science that studies particular things. While science and psychology may discuss humanity, sociology discusses the necessary outworking of humanity and math discusses numbers, history is about particular people, places and times. History is not merely a recording of what particular people did at particular times though. It is also an explanation of why they did it. Finally, history is not even the mere listing of explanations. It places the whole of history into an explanatory framework from least significant to most significant.
This is the reason why history is really a science. If history were merely a listing of events without any kind of explanation, then it could not be a science. But these facts are united to an explanation. It is true that such explanations are open to doubt. But the fact that an explanation exists at all means that history must be a science. These explanations must count as some kind of knowledge. But since all knowledge is a part of some science or other, historical knowledge must belong to historical science.
History is not a demonstrative science. Our historical knowledge is gained by induction and inference to the best explanation. These are not deductions, so it is possible for the premises to be true and the conclusion false. For example, we might later discover evidence that a particular Egyptian king did not really exist at all. Such evidence would mean that our previous explanation of his name appearing in a king-list would change. But such things are possible.
There are two popular dangers that we can fall into when investigating history. The first is to set the standard of evidence too high. This is often done when comparing history with a demonstrative science such as natural science. We might also become too skeptical of historical claims because we are using the wrong standard of evidence. This happens when testimonial evidence is unfairly prejudiced against. The second error is to set the standard of evidence too low. This error rarely happens in academic settings unless politics is involved. It does happen with conspiracy theories and fringe theories. It is for this reason that academic historians often distance themselves from such people, even when they happen to be correct.
Next, I will finish my series on knowledge by briefly discussing skepticism.