Thomas Young

Thomas Young


by David F. Coppedge

Like Euler, Thomas Young was one of those rare individuals with such awesome intellectual powers it makes one marvel at the potential in one human brain.  And if one thinks intelligence leads to skepticism, Young would disagree.  He maintained his childlike faith and moral uprightness throughout his all-to-brief life of 56 years.  A good short biography of Thomas Young was written by Dan Graves in Scientists of Faith (Kregel, 1996).

Ready to marvel at Young’s mind?  At age two he could read, and by age four he had read through the Bible twice.  While a teen, he could read Greek, Latin, Hebrew, Persian, Syriac, and Chaldean.  At 14 he was tutoring others on the classics.  By age twenty he had also learned French, German, Spanish, Arabic and Italian.

While a teen he also taught himself calculus, studied the sciences, learned how to construct his own optical devices, and learned medicine.  He also studied art and learned to play the flute.  He was not a complete nerd, either; he could also ride horses, sing, and dance.  Once he walked over 170 miles to see an art exhibition.

Young is remembered for a number of major discoveries and accomplishments as an adult scientist.  He is considered the founder of physiological optics—the practice of relating optics to the biology of the eye.  He postulated that astigmatism was due to defects in the cornea, for instance, and predicted that the retina responds to color with three types of sensors.  He was the first to do a double-slit experiment in optics, demonstrating that light had the properties of a wave: the two beams interfere like waves, he found, producing a diffraction pattern on a screen. Albert Einstein wrote this about Thomas Young in 1979 in his preface to Newton’s Opticks:

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.

In addition, Young began use of the term energy in a published work in 1807 in which he developed a physical concept of energy.  He also developed a mathematical constant describing elastic energy, still known as Young’s Modulus (though it owes a debt to work by Leonhard Euler 80 years earlier).  Basically, it allows engineers to calculate the strain on a material when a known stress is applied (or vice versa), independent of the geometry of the material.  This revolutionized engineering strategies, according to Wikipedia.

Young’s literary skills were brought to bear in an important task: the deciphering of the Rosetta Stone which had been discovered in 1799.  He was the first to translate the complete text – adding Egyptian hieroglyphics to his phenomenal grasp of languages.  In addition, he studied the tides, revised a nautical almanac, classified diseases, devised a way to estimate doses of medicine for children, studied the heart and arteries, developed a way to tune instruments, produced actuarial tables for insurance, and wrote over 60 articles for the Encyclopedia Britannica.  Thomas Young was a true polymath – an expert at just about everything. Concerning his talents and life goals, he said:

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.

Graves describes Young as joyful, truthful, morally upright, happily married and focused.  He attributed his success to the religious tenets he was taught as a child.  Raised a Quaker, he later joined the Church of England, but remained somewhat private about his faith.  Graves sums up his life by saying, “Thomas Young’s joyful pursuit of knowledge, his impeccable moral character, and his zest for living life to its fullest make him a scientist of faith well worth remembering.”