“An essential distinction exists between two stages in the process of advancing our knowledge of the laws of physical phenomena; the first stage consists in observing the relations of phenomena, whether of such as occur in the ordinary course of nature, or of such as are artificially produced in experimental investigations, and in expressing the relations so observed by propositions called formal laws. The second stage consists in reducing the formal laws of an entire class of phenomena to the form of a science; that is to say, in discovering the most simple system of principles, from which all the formal laws of the class of phenomena can be deduced as consequences.”

— William John Macquorn Rankine

Source: "Outlines of the Science of Energetics," (1855), p. 121; Lead paragraph: Section "What Constitutes A Physical Theory"

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William John Macquorn Rankine 28

civil engineer 1820–1872

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“A physical theory, like an abstract science, consists of definitions and axioms as first principles, and of propositions, their consequences; but with these differences:—first, That in an abstract science, a definition assigns a name to a class of notions derived originally from observation, but not necessarily corresponding to any existing objects of real phenomena, and an axiom states a mutual relation amongst such notions, or the names denoting them; while in a physical science, a definition states properties common to a class of existing objects, or real phenomena, and a physical axiom states a general law as to the relations of phenomena; and, secondly,—That in an abstract science, the propositions first discovered are the most simple; whilst in a physical theory, the propositions first discovered are in general numerous and complex, being formal laws, the immediate results of observation and experiment, from which the definitions and axioms are subsequently arrived at by a process of reasoning differing from that whereby one proposition is deduced from another in an abstract science, partly in being more complex and difficult, and partly in being to a certain extent tentative, that is to say, involving the trial of conjectural principles, and their acceptance or rejection according as their consequences are found to agree or disagree with the formal laws deduced immediately from observation and experiment.”

William John Macquorn Rankine (1820–1872) civil engineer

Source: "Outlines of the Science of Energetics," (1855), p. 121; Second paragraph

“[Biology has] become the paramount science, exceeding other disciplines, including physics and chemistry at least, in the creative tumult of its disciplines and disputations. […] I'll also be so bold at this point to suggest that we are now at the edge of establishing the two fundamental laws of biology: The first law is that all of the phenomena of biology, the entities and the processes, are ultimately obedient to the laws of physics and chemistry. Not immediately reducible to them, but ultimately consistent and in consilience with them, by a cause and effect explanation. The second law is that all biological phenomena, these entities and processes that define life itself, have arisen by evolution through natural selection.”

Edward O. Wilson (1929) American biologist

Talk at the 50th anniversary of New Scientist magazine (2006).

“Physics is essentially an intuitive and concrete science. Mathematics is only a means for expressing the laws that govern phenomena.”

Albert Einstein (1879–1955) German-born physicist and founder of the theory of relativity

From Lettre à Maurice Solvine, by A. Einstein (Gauthier-Villars: Paris 1956)
Attributed in posthumous publications, Albert Einstein: A guide for the perplexed (1979)

“As is known, scientific physics dates its existence from the discovery of the differential calculus. Only when it was learned how to follow continuously the course of natural events, attempts, to construct by means of abstract conceptions the connection between phenomena, met with success. To do this two things are necessary: First, simple fundamental concepts with which to construct; second, some method by which to deduce, from the simple fundamental laws of the construction which relate to instants of time and points in space, laws for finite intervals and distances, which alone are accessible to observation”

Bernhard Riemann (1826–1866) German mathematician

can be compared with experience
Die partiellen Differentialgleichungen der mathematischen Physik (1882) as quoted by Robert Édouard Moritz, Memorabilia Mathematica; Or, The Philomath's Quotation-book https://books.google.com/books?id=G0wtAAAAYAAJ (1914) p. 239

“Economic theory, since the time of the Physiocrats, has endeavored to get rid of the human will and to explain economic phenomena in terms of physical and hedonic forces. The human will had been the main reliance of the Mercantilists and of the economic theory of the Church fathers. But the will was arbitrary, capricious and contrary to natural laws. There were two stages of these physical theories which attempted to get away from the will:-the natural rights arld physical equilibrium stage of foreordained evolution of Quesnay, Adam Smith and Karl Marx, and the natural selection stage of blind evolution that followed Darwin, whose distinguished exponent in economics is Veblen. The theorists of each stage attempted to get rid of the human will and to explain economic phenomena as the working out of natural forces, either foreordained or blind. It was a concept of society as the natural growth of a mechanistic equilibrium.”

John R. Commons (1862–1945) United States institutional economist and labor historian

Source: Legal foundations of capitalism. 1924, p. 376

“The world of experience, both physical and psychic, is entirely composed of elements - spatial, tactile, accoustical, thermal, etc. Combinations of these elements make up different "phenomena", both psychic and physical. If the law of causality, inferred for all these phenomena - i. e. for the world of elements connected by various relations - is applicable to "things in themselves" serving as an immediate link between "phenomena" and "things", it is clear that "phenomena" and "things in themselves" are of the same nature. "Things in themselves" would then represent a direct continuation of the world of empirical elements and in fact would be only combinations of elements.”

Alexander Bogdanov (1873–1928) Physician, philosopher, writer

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

“We define law, using the word in the philosophic sense, as the constant relation discoverable in a series of phenomena.”

Michel Bréal (1832–1915) French philologist

Source: Essai de semantique, 1897, p. 11

“Doubt about the fact that insight wholesomeness consists of simply observing the presently arising mental and physical phenomena is also skeptical doubt. This doubt is so subtle that it is rarely detected but is instead mistaken for investigation. This doubt masquerades as analytical knowledge. The commentary on Netti Yuttihāra explains as follows: "Doubt appears in the guise of investigation."”

Mahasi Sayadaw (1904–1982) Burmese Buddhist philosopher

Source: Manual of Insight (1945), p. 64

“The law has outgrown its primitive stage of formalism when the precise word was the sovereign talisman, and every slip was fatal.”

Benjamin N. Cardozo (1870–1938) United States federal judge

Wood v. Lucy, Lady Duff-Gordon, 222 N.Y. 88, 91; 118 N.E. 214 (N.Y. 1917)
Judicial opinions
Context: The law has outgrown its primitive stage of formalism when the precise word was the sovereign talisman, and every slip was fatal. It takes a broader view to-day. A promise may be lacking, and yet the whole writing may be "instinct with an obligation," imperfectly expressed. If that is so, there is a contract.

“In thermodynamics as well as in other branches of molecular physics, the laws of phenomena have to a certain extent been anticipated, and their investigation facilitated, by the aid of hypotheses as to occult molecular structures and motions with which such phenomena are assumed to be connected.”

William John Macquorn Rankine (1820–1872) civil engineer

Source: A Manual of the Steam Engine and Other Prime Movers (1859), p. 31
Context: Hypothesis Of Molecular Vortices. In thermodynamics as well as in other branches of molecular physics, the laws of phenomena have to a certain extent been anticipated, and their investigation facilitated, by the aid of hypotheses as to occult molecular structures and motions with which such phenomena are assumed to be connected. The hypothesis which has answered that purpose in the case of thermodynamics, is called that of "molecular vortices," or otherwise, the "centrifugal theory of elasticity. (On this subject, see the Edinburgh Philosophical Journal, 1849; Edinburgh Transactions, vol. xx.; and Philosophical Magazine, passim, especially for December, 1851, and November and December, 1855.)

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William John Macquorn Rankine 28

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