Standing room only

A minor enduring meme of the 20th century has been the idea that the entire population of the world would fit on the Isle of Wight. Depending on assumptions, population growth appears to have made this obsolete around 1970, hence the title of John Brunner's 1968 dystopian SF novel Stand on Zanzibar.  I haven't been able to trace the precise origin of the Isle of Wight version of the meme, but the earliest citation I can find at this instant is to 1886:

... when we remember that the whole human family, every man, woman, child  on earth this day, could comfortably stand on the Isle of Wight ...
The Three First Chapters of Human History, The Very Rev. H Martyn Hart, Dean of Denver, Colorado, The Quiver, p239, 1886

Any advances welcome!

A number of early 20th century citations stem from a source a decade later, in the address of Sir John Wolfe Barry on his assumption of the Presidency of the Institution of Civil Engineers:

One is apt to get lost with these figures of millions of our fellow-subjects, and to think for an instant that our own is the culminating epoch of the world's history, and that over-population stares us in the face. This is a merely parochial idea, the absurdity of which can be realised when we remember that the population of the world can stand upon the Isle of Wight.
- Sir John Wolfe Barry, Minutes of Proceedings of the Institute of Civil Engineers, Volume 127, Session 1896-97, Part 1. Speech given November 1896.

One particular expression of the meme was the rather odd fantasy novel All Moonshine (Richard Whiteing, 1907). The narrator of All Moonshine goes to sleep while obsessing about war and world population, particularly focusing on a statistic he has seen ...

" It has been calculated that, at four persons to the square yard, the entire population of the globe, standing shoulder to shoulder, could find room and to spare in the Isle of Wight."

... and wakes up to a strange phenomenon, the populations of the world coming to visit the Island and play out their conflicts in astrally projected form, the narrator meanwhile falling in love with one of the astral visitors, the South Sea woman Nykie. It's highly polemical, both anti-war, and dismissive of the dangers of overpopulation. The reviewer of the Boston-based The Independent (a journal whose religious roots gave it a mystical leaning) loved it ...

We have had some very remarkable literary works published in England since I sent my latest article to The Independent. One of the most remarkable is the novel called "All Moonshine," written by Richard Whiteing and published by Messrs. Hurst & Blackctt, of London. I have called this book a novel because it presents itself to the reading world merely as such, but the name of novel would certainly not prepare the reader for such an extraordinary literary production as that which Mr. Whiteing has given to the world. It is at once a dream-story, a love-story, a poetic allegory in prose, and a rapturous anticipation of of a time soon to come when mankind is to be freed from the devastations of the war spirit. It is sometimes a satire, sometimes a prose-poem, sometimes a fairy tale, and the reader absorbed in its pages finds himself unable to say in which of these fields of literary production the author makes the greatest success. The love-story, which runs thru and keeps together the whole narrative, is in fact a continuation of a novel, “The Island,” written by Mr. Whiteing some years ago. For Mr. Whiteing's present purposes the gods annihilate both time and space, but not to make two lovers happy—rather to help them in the accomplishment of a magical work which is to make the whole world happy by reestablishing the reign of peace. The critic is spared all the trouble of raising questions as to possibilities or probabilities when dealing with the dream-story, which proclaims itself to be "All Moonshine". The reader will find  himself carried away by the story in all its moods and and will fancy many a time that he is actually looking on sonic of the marvelous scenes which the author causes to pass, panorama-like, before his eyes. All the brilliant peculiarities of Whiteing's style, peculiarities which have made for him a distinct reputation, are shining thru the pages of this book. The author is now humorous, now melancholy, now sarcastic. now grimly severe, and in each mood he seems to find the same felicities of expression. “All Moonshine" may, of course, be classed among what used to be called novels with a purpose, but in many even of the most successful and famous novels which used to be described by that name the reader sometimes found that the purpose over-shadowed or almost extinguished the story and that he was only reading a tract put into allegorical form. This fault cannot certainly be found with Mr Whiteing's new story, because we feel from first to last the deepest interest in the hero and the astral Nyleia [sic], notwithstanding the devotion which they both display to the promulgation of the arts of peace, and notwithstanding also the magical means by which the crusade for peace is supposed to make its way. Richard Whiteing has indeed long been recognized as a man not merely endowed with great talents, but with that gift which must be called genius, and I feel well convinced that "All Moonshine" will give the world of readers another reason for admitting him to that limited circle of living authors on whom such praise is fittingly bestowed.
- The Independent, Volume 63, page 1420, 1907

... but the NY Times Saturday Review was less impressed:

The first in point of importance is Richard Whiteing's " All Moonshine," published by Messrs. Hurst & Blackett, and distinctly a noteworthy book, though it must be confessed It is also an exasperating one. Mr. Whiteing in his typical manner of "No. 5 John Street" leads us through a story which obviously does not mean very much to him, and consequently cannot mean very much to us, for the sake of showing us his point of view on some serious Question and for the sake of teaching us some sort of lesson ... Who could hope to reconcile us to a book the action of which takes place almost entirely in a dream — and it is another relic of childish taste that we resent dream books nearly as bitterly as books with evident morals — the heroine of which is a South Sea Islander in her astral form, and all the rest of the characters astrals, too? Who could make us read with conviction thumb-nail sketches of all the world as seen by the dream-hero ...
- New York Times Saturday Review of Books and Art, further citation details unfindable

All Moonshine (Richard Whiteing, pub. Hurst and Blackett, 1907, Internet Archive ID allmoonshine00whitgoog).

The Island, mentioned by the first reviewer, is Whiteing's 1888 satirical fantasy in which the narrator, disaffected with London life, flees civilization and is shipwrecked on Pitcairn Island. There, guided by Victoria, the Chief Magistrate's daughter (the same character who later appears as "Nykie" in All Moonshine) he compares the Edenic socialistic lifestyle with Western culture, and departs a wiser man. In the light of recent revelations about the culture and mores of Pitcairn, the book's idyllic picture makes horribly ironic reading. See The Island, Or, An Adventure of a Person of Quality (Richard Whiteing, pub. Tauchnitz, 1888, Internet Archive ID islandoranadven01whitgoog).

The Island has an immediate sequel, No. 5 John Street (1899, Internet Archive ID nojohnstreet00whitgoog) in which the situation is reversed. The narrator of The Island, Lord —, having died, his friend is asked to report back to the Pitcairn islanders on life in London, experiencing a deal of London low-life in the process.

- Ray