Tennyson and Babbage? No! Trevelyan

From the preface to Edward Cook’s More Literary Recreations (1919), page xiii:

In [my previous book’s] chapter about “The Second Thoughts of Poets” … I fathered on Babbage a delightful emendation of two lines in Tennyson’s “Vision of Sin,” which I now restore to its rightful author. The emendation is to be found in Letter vii. of The Competition Wallah. It is attributed to “a friend who is passionately devoted to the study of the laws of sanitation and mortality. He carries his enthusiasm on the subject so far as to tinge with it his view of every conceivable matter — religious, political, and literary. He once wrote an anonymous letter to the Laureate, commenting on the lines in the Vision of Sin:

Every moment dies a man, / Every moment one is born.

He observed, with great truth, that if this statement were correct the population of the world would remain stationary, and urged the poet to alter the lines thus:

Every moment dies a man, / And one and one-sixteenth is born.

He owned that the exact figure was one, decimal point, ought, four, seven; but (as he said) some allowance must be made for metre.” I must hope that Sir George Trevelyan will forgive me for having invested his jeu d’esprit with a mythical origin.

Indeed the anecdote, exactly as quoted, appears in George Trevelyan’s The Competition Wallah (1864), at the end of the seventh letter, titled “About Calcutta and its Climate.” This comic essay was first published in Macmillan’s Magazine 9:49 (November 1863), pp. 117–135, datelined “April 12, 1863.”

The false attribution to Babbage was likely originated by David Ker in Harper’s Magazine 81:483 (August 1890), p. 486. Ker presents his version as a “story, which, if not literally true, certainly deserves to be so.”

The attribution may have been suggested by the fact that Babbage had authored in 1826 A Comparative View of the Various Institutions for the Assurance of Lives (a treatise on the mathematics of life insurance), which originated this widely reprinted observation:

Nothing is more proverbially uncertain than the duration of human life, when the maxim is applied to an individual; yet there are few things less subject to fluctuation than the average duration of a multitude of individuals. … Among the inhabitants of a kingdom, the uniformity is such, that the excess of deaths in any year above the average number seldom exceeds a small fractional part of the whole.