Thomas Young (scientist)
Thomas Young (13 June 1773 – 10 May 1829) was an English genius and polymath, admired by, among others, William Herschel and Albert Einstein. He is famous for having partly deciphered Egyptian hieroglyphs (specifically the Rosetta Stone) before Jean-Francois Champollion eventually expanded on his work.
- A permanent alteration of form limits the strength of materials with regard to practical purposes, almost as much as fracture; since, in general, the force which is capable of producing this effect is sufficient, with a small addition, to increase it till fracture takes place.
- I have resolved to confine my studies and my pen to medical subjects only. For the talents which God has not given me, I am not responsible, but those which I possess, I have hitherto cultivated and employed as diligently as my opportunities have allowed me to do ; and I shall continue to apply them with assiduity, and in tranquillity, to that profession which has constantly been the ultimate object of all my labours.
- Letter X: Reply to the Edinburgh Reviewers, Miscellaneous works of the late Thomas Young (1855), p. 215
- I met with an accident about five weeks ago in London, which has prevented my walking ever since, and I think I broke one of the metatarsal bones; this has been a favourable circumstance, for it has increased my literary application in a considerable degree. I have been studying, not the theory of the winds, but of the air, and I have made observations on harmonics which I believe are new. Several circumstances unknown to the English mathematicians which I thought I had first discovered, I since find to have been discovered and demonstrated by the foreign mathematicians; in fact, Britain is very much behind its neighbours in many branches of the mathematics: were I to apply deeply to them, I would become a disciple of the French and German school; but the field is too wide and too barren for me.
- Letter to Dr. Bostock (June, 1798) as quoted by George Peacock, Life of Thomas Young (1855)
- This statement appears to us to be conclusive with respect to the insufficiency of the undulatory theory, in its present state, for explaining all the phenomena of light. But we are not therefore by any means persuaded of the perfect sufficiency of the projectile system: and all the satisfaction that we have derived from an attentive consideration of the accumulated evidence, which has been brought forward, within the last ten years, on both sides of the question, is that of being convinced that much more evidence is still wanting before it can be positively decided. In the progress of scientific investigation, we must frequently travel by rugged paths, and through valleys as well as over mountains. Doubt must necessarily succeed often to apparent certainty, and must again give place to a certainty of a higher order; such is the imperfection of our faculties, that the descent from conviction to hesitation is not uncommonly as salutary, as the more agreeable elevation from uncertainty to demonstration. An example of such alternations may easily be adduced from the history of chemistry. How universally had phlogiston once expelled the aërial acid of Hooke and Mayow. How much more completely had phlogiston given way to oxygen! And how much have some of our best chemists been lately inclined to restore the same phlogiston to its lost honours! although now again they are beginning to apprehend that they have already done too much in its favour. In the mean time, the true science of chemistry, as the most positive dogmatist will not hesitate to allow, has been very rapidly advancing towards ultimate perfection.
- Miscellaneous Works: Scientific Memoirs (1855) Vol. 1, ed. George Peacock & John Leitch, p. 249
- When I was a boy, I thought myself a man. Now that I am a man, I find myself a boy.
- as quoted by Horatio B. Williams, Thomas Young, The Man and Physician, J. Opt. Soc. Am. 20, 35-49 (1930).
"Outlines of Experiments and Inquiries Respecting Sound and Light" (1800)
From the Philosophical Transactions In a Letter addressed to Edward Whittaker Grey, M.D. Sec. R.S. Read January 16th
- The well known elevation of the pitch of wind instruments, in the course of playing, sometimes amounting to half a note, is not, as is commonly supposed, owing to any expansion of the instrument, for this should produce a contrary effect, but to the increased warmth of the air in the tube.
- It may hereafter be considered how far the excellent experiments of Count Rumford, which tend very greatly to weaken the evidence of the modern doctrine of heat, may be more or less favourable to one or the other system of light and colours.
- It is surprising that so great a mathematician as Dr. Smith could have entertained for a moment, an idea that the vibrations constituting different sounds should be able to cross each other in all directions, without affecting the same individual particles of air by their joint forces: undoubtedly they cross, without disturbing each other's progress; but this can be no otherwise effected than by each particle's partaking of both motions. If this assertion stood in need of any proof, it might be amply furnished by the phenomena of beats, and of the grave harmonics observed...
An Introduction to Medical Literature, Including a System of Practical Nosology (1823)
- There is no study more difficult than that of physic: it exceeds, as a science, the comprehension of the human mind: and those who blunder onwards, without attempting to understand what they see, are often very nearly on a level with those, who depend too much on imperfect generalisations, applied to facts, which can scarcely be subjected to any well marked analogy. Hence it may happen, that talents and labour may become useless for want of a proper direction... To assist in furnishing the student with a sufficient direction... is the principal object of this work.
- p. 2
- Physic is one of those departments, in which there is frequent necessity for the exercise of an incommunicable faculty of judgment, and a sagacity, which may be called transcendental, as extending beyond the simple combination of all that can be taught by precept. Nor is there any other mode of cultivating these powers, than by pursuing a much more extensive range of elementary study, than appears, to a common and superficial observer, to be in any way connected with the immediate objects of the profession.
- p. 5
Quotes about Young
- I may here refer to a curious mathematical calculation by Dr. Thomas Young, to the effect, that if three words coincide in two different languages, it is ten to one they must be derived in both cases from some parent language, or introduced in some other manner. "Six words would give more," he says, "than seventeen hundred to one, and eight near 100,000, so that in these cases the evidence would be little short of absolute certainty."
- Reflexion, refraction, the formation of images by lenses. the mode of operation of the eye, the spectral composition and recomposition of the different kinds of light the invention of the reflecting telescope, the first foundations of colour theory, the elementary theory of the rainbow pass us by in procession, and finally come his of the colours of thin films as the origin of the next great theoretical advance, which had to await, over a hundred years, the coming of Thomas Young.
Life of Thomas Young (1855)
- It is now more than twenty years since I somewhat rashly undertook to write the Life of Dr. Young. ...The undertaking was consequently abandoned, and it was proposed to transfer it to other hands; but it was not found easy to secure the services of a person who possessed sufficient scientific knowledge to enable him to write the life of an author whose works were so various in their character and not unfrequently so difficult to understand and analyse, as those of Dr. Young.
- Preface, p. vii
- It was the kindred science of sound which had suggested to Young his principle of interference, and he was under a similar obligation to the same science for the suggestion of the principle which formed the first step in the solution of the great problem of double refraction.
- Ch. XII Optical Discoveries.—Second Epoch, p.375
- We propose... to call the attention of our readers to some of the more remarkable Memoirs, or Philosophical Essays, of Dr. Young, which have not elsewhere been noticed; selecting those which are distinguished... or which are otherwise calculated to show the extraordinary capacity which he possessed of solving the most difficult problems in the applications of mathematics to natural philosophy, by processes apparently the most inadequate to the purpose. He never confined himself to the beaten track of a systematic investigation. We find in his writings no symmetrical formula or analytical refinements. There is no seeking after generalities, when the particular question which he has in hand does not require them; whilst every expedient is freely resorted to, however irregular and unusual, if it serves the purpose which he has in view. Important and difficult steps are passed over as manifest, terms are neglected as insignificant, analogies take the place of proofs, and we are surprised to find ourselves at the end of an investigation, even within the limits of space which would commonly be deemed hardly sufficient to master the difficulties which meet us at the beginning. But his rare sagacity hardly ever deserts him; and though he has occasionally been led to hasty and premature conclusions, or committed mistakes in numerical calculations, from the brevity and rapidity of his processes, yet nothing can be more surprising than the general soundness of his views of mechanical principles and their applications, and the correctness both of his philosophical and numerical results.
- Ch. 15 Miscellaneous Memoirs, pp.416-417
- A Memoir on Hydraulics, printed in the Philosophical Transactions for 1808, was introductory to another in the same Collection for the following year, on the Functions of the Heart and Arteries. The connection between these subjects was considered by him... sufficiently close to give them both a professional character, and thus to exempt them from the restriction which he had imposed upon the class of publications which alone should be allowed to appear under his own name. ...Few persons can be found ...with a union of acquirements so remote from each other as to be able to prosecute an inquiry of this nature, or to judge of the correctness of the conclusions to which it leads; but as such it was exactly suited to Dr. Young, who delighted in questions so obscure and difficult, where his various knowledge and bold spirit of speculation had full room for their exercise.
- Ch. XV Miscellaneous Memoirs, p. 417