There is no primary source evidence that Wilde made this statement.
One of the most celebrated quotations by anyone is the remark attributed to Oscar Wilde at New York Customs at the start of his lecture tour of America in 1882.
But what exactly did he say, and what is the source of the quotation?
Until my research some years ago the earliest source typically cited (if a source was given at all) was Frank Harris' Oscar Wilde: His Life and Confessions (1916), Vol. 1, Chap. V. For example, this is the source given in The Oxford Dictionary of Quotations (1999) p. 819, and in Beckson.
However, in 2002 (in a review for the OWSOA now superseded by this article) I identified what is still the earliest known allusion to the remark in print or otherwise. It appeared in a book published by Arthur Ransome a year earlier than Harris; the source is:
The date of this book (1912) immediately provides us with a primary reason for doubt:
The first reference to the quotation appeared thirty years after it was allegedly made.
Not only is it suspicious that it took thirty years for the quotation to emerge, it is equally surprising that there is no contemporary evidence for it, as many of Wilde's remarks were seized upon by the press in 1882 and widely, often immediately, reported.
There is also no mention of it in interviews given by Wilde, including approximately a hundred given to American journalists in 1882, many soon after his arrival where he was widely quoted. Neither does Wilde make any reference to the remark in any of the over 1500 letters of his that survive, including those at the time from New York that are often detailed. Indeed, there is no other written or oral record of the remark by anyone else during Wilde's time.
When Wilde died in November, 1900, it did not take long for the first biography to be published. This was: Oscar Wilde; the story of an unhappy friendship, (1902) by his devoted friend Robert Sherard. The biography does not mention the incident, but does report the "disappointed in the Atlantic" comment that Wilde did make upon arrival.
Another biography In Memoriam, Oscar Wilde (1905) by André Gide, Franz Blei, and Ernest La Jeunesse, refers to Wilde's genius several times (pp. 49, 87, 91, 101) and even quotes Wilde on French customs officers (p. 55); but still there is no mention of the New York incident. The only biographical references to the remark are post-Ransome. So it is to him we must return. Below is what Ransome wrote and, unfortunately, he gave no source:
Arthur Michell Ransome was an English author and journalist, best known for the Swallows and Amazons series of children's books.
Ransome wasn't alive at the time of the alleged remark and, indeed, never met Wilde. In 1912, he wrote his Critical Study of Wilde with the assistance and support of Robert Ross, Wilde's literary executor.
On balance I believe we can take Ransome at face value. There is no reason to suspect that the unassuming son of a history professor would have fabricated the incident. After all, his book, A Critical Study, is just that: a literary study—it is not primarily autobiographical nor makes any attempt at levity or sensation.
However, we should note that Ransome cites the remark as reported speech and not as a direct quotation. Should we make anything of this? Does it, perhaps, hint at a conversational origin for the quote? Or is Ransome implying a figurative 'announcement' that Wilde was making by his presence, rather than a spoken one?
I think neither: Ransome places the remark amid three statements, two of which are factual, including a known quotation (disappointed in the Atlantic) and he is specific about the circumstances. It is safe to infer that Ransome intended the remark to be an actual quotation, so he appears to be as good as his source.
It is reasonable to assume that Ransome came across the incident in his research for the book. It is unlikely that the story was in writing at the time—at least no prior printed or manuscript evidence has been found.
It is more likely that Ransome learned of the story orally. He talked to Wilde's two sons, as well to others who had known Wilde, from whom, as he put it in the Preface, he gained "valuable reminiscence".
Ross generously allowed Ransome access to Wilde's correspondence and Ross' influence is apparent in the book, indeed Ransome dedicated to him. A good example of this influence can be seen in the relevant passage itself, in which Ransome cites a Wilde lecture 'Art and the Handicraftsman', which was a title never used by Wilde but created by Ross for his Complete Works some years earlier (see Lecture Titles). As an intimate friend of both Ransome and Wilde, Ross, even though he did not meet Wilde himself until well after 1882, is the most likely source.
Unfortunately, no one to whom Ransome is likely to have spoken, including Ross, could have known about an incident at New York harbor first-hand. Thus we have a second major reason for doubt:
The remark was based on hearsay.
It is just possible that the story might have existed for some time before Ransome, perhaps with an element of urban mythology, having undergone a corruption or misattribution similar to several of Wilde's remarks. One is reminded that much history, especially quotation, is apocryphal: too good not to have been said. It would be a seductive notion if any oral history of the incident included Wilde himself, but there is no evidence for it. However, the idea introduces the possibility that Wilde, even if he did not make the remark at New York Customs, might later have claimed to have done, or perhaps wished that he had. It would not be unlike Wilde to revel in the public's belief of a rumor about himself. But if this is so, why did the rumor not emerge until 1912?
More likely is that the story emerged as Ransome was preparing his book, either intentionally created as apropos to Wilde (perhaps by Ross) or innocently misremembered.
But lacking contemporary evidence it is not possible to be definitive about whether the remark is genuine, and reasonable inference must be towards doubt.
Research for an earlier source is ongoing.
 See also Homage to Genius
* UPDATE: Since publishing this article I have uncovered additional information about Wilde's arrival in New York, including the identity of the Customs Official who attended him (and he said nothing about it either).
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