The first fundamental rule of historical science and research, when by these is sought a knowledge of the general destinies of mankind, is to keep these, and every object connected with them, steadily in view, without losing ourselves in the details of special inquiries and particular facts, for the multitude and variety of these subjects is absolutely boundless; and on the ocean of historical science the main subject easily vanishes from the eye. ...In the higher grades of academic instruction, the lessons on history must vary with each one's calling and pursuits ...[T]he archives of many a state would alone furnish occupation for more than a man's life. ...The first fundamental rule ...to keep the attention fixed on the main subject, and not to let it be distracted or dissipated by a number of minute details—concerned more the method of historical science. The second rule regards the subject and purport of history... [W]e should not wish to explain every thing. Historical tradition must never be abandoned in the —otherwise we lose all firm ground and footing... [W]e have nothing to do but to record, as it is given, the best and safest testimony which tradition, so far as we have it, can afford... Extremely hazardous is the desire to explain every thing, and to supply whatever appears a gap in history—for in this propensity lies the first cause and germ of all those violent and arbitrary hypotheses which perplex and pervert the science of history far more than the open avowal of our ignorance, or the uncertainty of our knowledge: hypotheses which give an oblique direction, or an exaggerated and false extension to a view of the subject originally not incorrect. And even if there are points which appear not very clear to us, or which we leave unexplained—this will not prevent us from comprehending, so far... as the limited conception of man is able, the great outline of human history, though here and there a gap should remain.

The historical approach to understanding of scientific fact is what differentiates the scholar in science from the mere experimenter.

To understand a science it is necessary to know its history.

The first rule is that you can't really know anything if you just remember isolated facts and try and bang 'em back. If the facts don't hang together on a latticework of theory, you don't have them in a usable form.

I fully agree with you about the significance and educational value of methodology as well as history and philosophy of science. So many people today - and even professional scientists - seem to me like somebody who has seen thousands of trees but has never seen a forest. A knowledge of the historic and philosophical background gives that kind of independence from prejudices of his generation from which most scientists are suffering. This independence created by philosophical insight is - in my opinion - the mark of distinction between a mere artisan or specialist and a real seeker after truth.
[Correspondance to Robert Thorton in 1944]

This tendency of mankind to do, in general, this year what it did last, in spite of changes in some one department of life, — such as substituting a president for a king, traveling by rail instead of on horseback, or getting the news from a newspaper instead of from a neighbor, — results in what is called the unity or continuity of history. The truth that no abrupt change has ever taken place in all the customs of a people, and that it cannot, in the nature of things, take place, is perhaps the most fundamental lesson that history teaches. Historians sometimes seem to forget this principle, when they claim to begin and end their books at precise dates.

A modern theory of knowledge which takes account of the relational as distinct from the merely relative character of all historical knowledge must start with the assumption that there are spheres of thought in which it is impossible to conceive of absolute truth existing independently of the values and position of the subject and unrelated to the social context. Even a god could not formulate a proposition on historical subjects like 2 x 2 = 4, for what is intelligible in history can be formulated only with reference to problems and conceptual constructions which themselves arise in the flux of historical experience.

In our time of ever-increasing specialization, there is a tendency to concern ourselves with relatively narrow scientific problems. The broad foundations of our present-day scientific knowledge and its historical development tend to be forgotten too often. This is an unfortunate trend, not only because our horizon becomes rather limited and our perspective somewhat distorted, but also because there are many valuable lessons to be learned in looking back over the years during which the basic concepts and the fundamental laws of a particular scientific discipline were first formulated.

There is a lesson to be learned from the history of sciences, technology and societies, if you look at the specific needs of each country at defining a scientific policy, policy that can not be the same everywhere: the basis of anything is education, so that people not only become qualified, but essentially become able to create new knowledge.