“Ressentiment is always to some degree a determinant of the romantic type of mind. At least this is so when the romantic nostalgia for some past era (Hellas, the Middle Ages, etc.) is not primarily based on the values of that period, but on the wish to escape from the present. Then all praise of the “past” has the implied purpose of downgrading present-day reality.”

"Quotes", The Educated Imagination (1963), Talk 3: Giants in Time

Source: Fiction Sets You Free: Literature, Liberty and Western Culture (2007), p. 18.

Patrick J. Geary, The Myth of Nations: The Medieval Origins of Europe, Princeton University Press, 2003

version in original Dutch (citaat van Johannes Bosboom, in Nederlands): ..hoe met de Romantische beweging na 1830 ook de liefde ontwaakte voor alles wat vroegere tijden — ook het tijdvak der middeneeuwen — voor den geest riepen en hoe daaruit de zucht ontsproot tot het verzamelen van voorwerpen, die van den smaak dier tijden getuigden. Ook hierin stond de gevierde Nuyen vooraan.
Quote of J. Bosboom, c. 1890; as cited in De Hollandsche Schilderkunst in de Negentiende Eeuw, G. H. Marius; https://ia800204.us.archive.org/31/items/dehollandschesch00mariuoft/dehollandschesch00mariuoft.pdf Martinus Nijhoff, s-'Gravenhage / The Hague, tweede druk, 1920, p. 108 translation from the original Dutch: Fons Heijnsbroek)
the studio of Bosboom was more or less a small museum, exposing his collected objects from the middle-ages
1890's

Variants: One of the schools in Tlön has reached the point of denying time. It reasons that the present is undefined, that the future has no other reality than as present hope, that past is no more than present memory . . . Another maintains that the universe is comparable to those code systems in which not all the symbols have meaning, and in which only that which happens every three hundredth night is true...
The history of the universe... is the handwriting produced by a minor god in order to communicate with a demon.
Tlön, Uqbar, Orbis Tertius (1940)
Context: One of the schools of Tlön goes so far as to negate time; it reasons that the present is indefinite, that the future has no reality other than as a present hope, that the past has no reality other than as a present memory. Another school declares that all time has already transpired and that our life is only the crepuscular and no doubt falsified an mutilated memory or reflection of an irrecoverable process. Another, that the history of the universe — and in it our lives and the most tenuous detail of our lives — is the scripture produced by a subordinate god in order to communicate with a demon. Another, that the universe is comparable to those cryptographs in which not all the symbols are valid and that only what happens every three hundred nights is true. Another, that while we sleep here, we are awake elsewhere and that in this way every man is two men.

On Eagle's Wings, 1977, p. 159
As of a Trumpet, On Eagle's Wings

Source: "Some Perplexities about time: with an attempted solution" (1925), p. 149. as cited in: Jonathan Gorman, "The transmission of our understanding of historical time." Historia Social y de la Educación 1.2 (2012): 129-152.

The Law of Mind (1892)
Context: Some minds will jump here jump to the conclusion that a past idea cannot in any sense be present. But that is hasty and illogical. How extravagant too, to pronounce our whole knowledge of the past to be mere delusion! Yet it would seem that the past is completely beyond the bounds of possible experience as a Kantian thing-in-itself.