“I was not influenced by composers as much as by natural objects and physical phenomena.”

Alexander Bogdanov, cited in: ‎James Patrick Scanlan, (1965). : Pre-revolutionary philosophy and theology. Philosophers in exile. Marxists and Communists. p. 398

Science and the Unseen World (1929)
Context: If to-day you ask a physicist what he has finally made out the æther or the electron to be, the answer will not be a description in terms of billiard balls or fly-wheels or anything concrete; he will point instead to a number of symbols and a set of mathematical equations which they satisfy. What do the symbols stand for? The mysterious reply is given that physics is indifferent to that; it has no means of probing beneath the symbolism. To understand the phenomena of the physical world it is necessary to know the equations which the symbols obey but not the nature of that which is being symbolised.... this newer outlook has modified the challenge from the material to the spiritual world.<!--III, p.30

volume I; lecture 35, "Color Vision"; 35-1 "The human eye"; p. 35-1
The Feynman Lectures on Physics (1964)

Ideology and Utopia (1929)
Context: This first non-evaluative insight into history does not inevitably lead to relativism, but rather to relationism. Knowledge, as seen in the light of the total conception of ideology, is by no means an illusory experience, for ideology in its relational concept is not at all identical with illusion. Knowledge arising out of our experience in actual life situations, though not absolute, is knowledge none the less. The norms arising out of such actual life situations do not exist in a social vacuum, but are effective as real sanctions for conduct. Relationism signifies merely that all of the elements of meaning in a given situation have reference to one another and derive their significance from this reciprocal interrelationship in a given frame of thought. Such a system of meanings is possible and valid only in a given type of historical existence, to which, for a time, it furnishes appropriate expression. When the social situation changes, the system of norms to which it had previously given birth ceases to be in harmony with it. The same estrangement goes on with reference to knowledge and to the historical perspective. All knowledge is oriented toward some object and is influenced in its approach by the nature of the object with which it is pre-occupied. But the mode of approach to the object to be known is dependent upon the nature of the knower.

Sixth Lecture, Statistical Problems in Physics, p. 187
Probability, Statistics And Truth - Second Revised English Edition - (1957)

The Chemical History of a Candle (1860)

A Preliminary Discourse on the Study of Natural Philosophy (1831)
Context: We must never forget that it is principles, not phenomena, — laws not insulated independent facts, — which are the objects of inquiry to the natural philosopher. As truth is single, and consistent with itself, a principle may be as completely and as plainly elucidated by the most familiar and simple fact, as by the most imposing and uncommon phenomenon. The colours which glitter on a soapbubble are the immediate consequence of a principle the most important, from the variety of phenomena it explains, and the most beautiful, from its simplicity and compendious neatness, in the whole science of optics. If the nature of periodical colours can be made intelligible by the contemplation of such a trivial object, from that moment it becomes a noble instrument in the eye of correct judgment; and to blow a large, regular, and durable soap-bubble may become the serious and praise-worthy endeavour of a sage, while children stand round and scoff, or children of a larger growth hold up their hands in astonishment at such waste of time and trouble. To the natural philosopher there is no natural object unimportant or trifling. From the least of nature's works he may learn the greatest lessons. The fall of an apple to the ground may raise his thoughts to the laws which govern the revolutions of the planets in their orbits; or the situation of a pebble may afford him evidence of the state of the globe he inhabits, myriads of ages ago, before his species became its denizens.
And this, is, in fact, one of the great sources of delight which the study of natural science imparts to its votaries. A mind which has once imbibed a taste for scientific inquiry, and has learnt the habit of applying its principles readily to the cases which occur, has within itself an inexhaustible source of pure and exciting contemplations. One would think that Shakspeare had such a mind in view when he describes a contemplative man as finding

As quoted in the opening lines of "The Adventures of Col. Daniel Boon; containing a Narrative of the Wars of Kentucke" in The Discovery, Settlement And present State of Kentucke (1784) http://digitalcommons.unl.edu/etas/3/ by John Filson
Context: Curiosity is natural to the soul of man and interesting objects have a powerful influence on our affections. Let these influencing powers actuate, by the permission or disposal of Providence, from selfish or social views, yet in time the mysterious will of Heaven is unfolded, and we behold our conduct, from whatever motives excited, operating to answer the important designs of heaven.

Lecture II : The Universal Categories, §3. Laws: Nominalism, CP 5.65
Pragmatism and Pragmaticism (1903)
Context: All nature abounds in proofs of other influences than merely mechanical action, even in the physical world. They crowd in upon us at the rate of several every minute. And my observation of men has led me to this little generalization. Speaking only of men who really think for themselves and not of mere reporters, I have not found that it is the men whose lives are mostly passed within the four walls of a physical laboratory who are most inclined to be satisfied with a purely mechanical metaphysics. On the contrary, the more clearly they understand how physical forces work the more incredible it seems to them that such action should explain what happens out of doors. A larger proportion of materialists and agnostics is to be found among the thinking physiologists and other naturalists, and the largest proportion of all among those who derive their ideas of physical science from reading popular books.