Things like this make me one cynical Wikipedian. In any event, I noticed an entry had been added to the bibliography to a random academic article:
Malone, Paul M. (2007) "My Own Private Apocalypse: Shinji Ikari as Schreberian Paranoid Superhero in Hideaki Anno's Neon Genesis Evangelion", pages 111-126 in Wendy Haslem, Angela Ndalianis, C. J. Mackie (eds.) Super/Heroes: from Hercules to Superman New Academia Publishing 9780977790845
As luck would have it (since it's in no library within 50 miles or on any of the usual ebook sources I checked), practically the entire book, including the entire article, was readable in Google Books: http://books.google.com/books?id=deiYbEbJY3UC
Malone uses the usual sources you would expect from an academic, hitting Sadamoto & Anno a little better than most, although his reliance on Napier is a bit dangerous (she doesn't understand Eva very well) and Kotani is nuts (her views are pretty weird even in summary).
What is interesting is that he bases the article on a German madman, Daniel Paul Schreber (https://secure.wikimedia.org/wikipedia/en/wiki/Daniel_Paul_Schreber), who... wrote a book on his madness and worldview. A book that was a favorite of Carl Jung, who recommended it to Sigmund Freud who discussed it extensively; Jungians have discussed it ever since, apparently. The psychiatrist put in charge of Schreber published a book entitled Gehirn und Seele. Freud & Jung have been available in Japanese for forever, of course, and Schreber was translated into Japanese in 1991. Hm.
Malone seems to seriously overreach when he says Anno actually underwent therapy - his two references neither say that* - but does provide one solid-sounding reference for his claim that most Japanese therapists would be Jungian. Malone carefully says that "Evangelion is clearly not directly based on Schreber's memoirs", but... why not?
* I am aware that the Nobi interview I link later on does include a line where Anno says he went to see 'a doctor', but that was after NGE TV finished and a source unlisted by Malone.
At this point, I recall one source not available to Malone writing in 2005, Anno's interview with Nobi http://forum.evageeks.org/viewtopic.php?p=421849#421849
At that time I consulted a bit with my friends. When I asked if there was something composed by a madman, I was loaned a "Bessatsu Takarajima" [1] volume on mental illness. It was an "easy and reasonable" book [イージーでリーズナブルな本] (laughs), but inside it there was a poem written by a madman. That was extremely good. When I read the poem I had a strong impression, as though this was the first time that I had come close. I had a feeling like a light glinting upon the tip of a sharp knife. It was certainly not the feeling of an ordinary man. That was good. If I think about it now, this sort of 'capacity' was [already] within me (laughs). [??2] It's mad to believe that the writings of a madman are of the highest quality. I read that [poem] and was filled with images; I was able to write [Rei's monologue] in one sitting.
Well! Maybe Anno had not read Schreber directly, but he clearly read a poem by *some* madman, and why couldn't this pop psychology book be quoting Schreber? Malone mentions, in the context of Eva's use of classical music, that Schreber often recited poems or sang songs to cope, which makes it plausible he might've *written* some poems too, and put them in his memoirs.
As it happens, said memoirs are also available, fully searchable, in Google Books: http://books.google.com/books?id=BPdL_BOnKOIC 'poetry' turns up nothing useful, and 'poem' turns up only one useful hit on page 119, a poem brought to Schreber by his wife. That is, not written by him, the madman. Not good, but not damning either; perhaps the detailed provenance was lost in translation or Anno didn't notice or forgot or was being vague as he spoke extemporaneously. The poem goes:
Ere true peace can reach you -
God's still and silent peace -
The peace life never giveth
Nor worldly joys beneath,
It needs God's arm must strike
A blow and wound you deep,
So that you cry: Have mercy,
God, have mercy on my days,
It needs a cry must ring,
Ring from your soul
And darkness be within you,
As 'fore the world's first day.
It needs that crushing pain
Must wholly vanquish you,
And not a lonely tear be left
In your poor wretched soul.
And when you're done with weeping
And weary art, so weary,
Then comes to you a faithful guest
God's still and silent peace.
You can't tell me that some of that doesn't sound Eva-like.
Short of finding more info on that 'Bessatsu Takarajima', though, I had only one last thing to try. As a pop psych book, I would *strongly* expect some Japanese otaku to have found it and copied out the relevant poem online, as there can only be a few such books from the right time period and even fewer with poems. Such an otaku would be sure to list Schreber's name in connection with it, either following Anno's hypothetical mistake or to correct it.
en Wikipedia doesn't have a ja interwiki for Schreber's biography, and searching ja Wikipedia directly didn't turn up any kanji, so I simply searched for the Hideaki Anno kanji with "Daniel Schreber" and variants.
I found absolutely nothing. The combinations turned up a few pages, at best, discussing the American movie _Dark City_ (which apparently has a character named after Schreber). Searching for Schreber and Anno turned up nothing, Schreber and Eva turned up nothing, Schreber and NGE turned up nothing. Not the slightest speculation.
Oh dear. That rather puts the kibosh on my idea. It's far from the first such promising lead to pan out as nothing, but I still have hopes, so I have recorded the whole process here.
I have tried machine translation through Google Translate, but I don't have a lot of confidence in the results. What I can tell you is that there are 12 pages of writings in here from patients who were in the Murakami Hospital. Based on my preview via machine translation, there are a few poems which could have inspired Anno in writing "Rei's poem"; it's possible that it wasn't any single one.
