Should I use on or upon in the following sentence?
I remembered the story years later when I investigated the incident it was based on.
In this particular case, it makes no real difference. And if you’re one of those who feels that whenever you have the choice of two words of unequal lengths, indistinguishable in meaning, that you should always select the shorter of the two, then the choice is clear.
Others have noted that despite claims that on and upon are completely interchangeable, that there many places where you cannot use upon at all. It turns out there are also a few places where the reverse is true, that you cannot use on and must upon.
One such place is with phrasal verbs involving upon; there are also several non-verbal formulaic constructs associated with upon. Here are some of them:
to come upon
- 1827 Scott Tales of Grandfather 1st Ser. viii, To come upon him suddenly and by night.
- 1832 Tennyson Lady of Shalott iii, in Poems (new ed.) 15 ‘The curse is come upon me,’ cried The Lady of Shalott.
- 1886 J. McCarthy & R. C. Praed Right Hon'ble III. xxviii. 39 It came upon her now that something subtler‥lay at the root.
- 1850 Tait's Edinb. Mag. Dec. 725/2 They might come upon me afterward, and make me pay up.
- 1820 Examiner No. 637. 414/2 She came upon us by surprise.
- 1849 T*ait's Edinb. Mag.* 16 154/1 The travellers soon came upon a village.
- 1865 J. W. Carlyle Lett. III. 256, I came upon Geraldine in Cheyne Row.
to fall upon
- 1858 E. H. Sears Athanasia III. v. 297 The church‥had fallen upon the belief that he [Christ] was soon to appear again.
- Also, to fall upon the enemy is not the same as to fall on the enemy.
to set upon (to attack, assail, fall violently upon)
- 1875 Jowett Plato (ed. 2) I. 356 This is the reason why my three accusers..have set upon me.
to stand upon
- 1854 Poultry Chron. 2 206 ‘Faint heart ne'er won fair lady’ is a good motto to stand upon.
- 1828 E. Bulwer-Lytton Pelham III. xii. 209 Lady Glanville was a woman of the good old school, and stood somewhat upon forms and ceremonies.
- 1889 ‘M. Gray’ Reproach of Annesley I. ii. i. 145 You stand upon a fanciful punctilio.
- 1889 F. Barrett Under Strange Mask II. x. 2 We were real friends, and only stood upon ceremony in our business relations.
to feel put-upon by an imposition
- 1996 Daily Express 1 Mar. 47/5 Dolores is revealed‥as a put-upon drudge who slaved for her employer.
- 2005 Observer 18 Sept. i. 23/3 Wallace's‥poor put-upon dog, Gromit.
upon a wind (a nautical term)
- 1810 Scott Let. 18 Mar. (1932) II. 313, I would‥endeavour to go as the sailors express it upon a wind i.e. make use of it to carry me my own way.
- 1846 H. Raikes Life Sir J. Brenton 328 Every ship‥made all the sail she could carry upon a wind.
once upon (a time)
- 1854 Poe The Raven Once upon a midnight dreary, while I pondered, weak and weary,
- Once upon a time, there lived ...
- Once upon an autumn eve, a wounded knight named Sieur Luc ...