Music and the Making of Modern Science

Though Isaac Newton considered poetry “ ingenious nonsense, ” music had a significant if

limited place in his intellectual world.^1 His youthful manuscripts demonstrate the scope

of his knowledge and interest. Later, at a critical point in his optical writings, he relied on

a musical analogy to compare the seven notes of the diatonic scale and the seven colors

he likewise attributed to the spectrum. A close examination of his use of this analogy

discloses its power and implicit limitations. Newton ’ s case may be read as a cautionary

tale about the way musical analogies can open possibilities but leave important matters

provocatively undecided.

Almost all of Newton ’ s musical writings are in a notebook he used during his under-

graduate period (1664 – 1666), spanning his annus mirabilis 1665, the year in which he

first grasped his celebrated insights about gravitation and light during an enforced stay at

home to avoid the plague.^2 In this notebook, Newton first compiled drafts that work out,

in intense and obsessive detail, fundamental definitions of musical intervals ( figure 8.1 ).

He includes circular diagrams resembling some in Descartes ’ s Compendium musicae ,

supporting the possibility that Newton studied that work, as he studied Descartes ’ s other

writings at the time.^3 Newton ’ s manuscript “ Of Musick ” clearly demonstrates his involve-

ment in the study of music as part of the quadrivium. Though brief, the work ’ s level of

detail and methodical enumeration of possibilities show the ways music was important to

him, not merely a perfunctory study.^4

Beyond summarizing commonplaces, the ordering and minute details of Newton ’ s

text register his unfolding sequence of further reflections. He begins by analogizing the

“ Clef or Key ” of a piece of music to the concept of “ an unit ” as mathematical center.

Turning then to the octave and the intervals within it, Newton considers their “ order of

concordance ” but goes beyond commonplaces about their ratios to an argument that is

interestingly physical in character: “ As too sudden a change from less to greater light

offends the eye ... so the sudden passing from grave to acute sounds is not so pleasant as

if it were done by degrees, because of too great a change of motion made thereby in the

auditory spirits. ”^5

8 Newton and the Mystery of the Major Sixth