I have a question about a belief which, although never completely debunked,
is now so dead that it is difficult to find any discussion of its history.
I refer to "ignis fatuus," which is New Latin for "fool's fire." The
believers called it "will-o'-the-wisp" or "foxfire," and believed it to be
the manifestation of a spirit, human or animal.
This subject is not well understood. Consider the definition of "foxfire"
given by the OED, and its attendant examples:
fox-fire. Now only U.S. The phosphorescent light emitted by decaying timber.
1824: J. P. Kennedy *Swallow Barn I. xxviii. 311 "The fox-fire---as the
country people call it---glowed hideously from the cold and matted bosom of
1853: Kane, Grinnell Exp. xxiv. (1856, p. 193), "The fox-fire of the Virginia
1872: E. Eggleston, End of World xxii, 210 "The 'fox-fire', rottng logs
glowing with a faint luminosity, startled her several times.
1920: J. J. Hunter: Trail Drivers of Texas (p. 149) "This is where you could
see phosphorescence (fox fire) on our horses' ears."
Of these, only the 1872 entry is due to decaying timber. The 1824 and 1853
examples are of "marsh gas" (also called "foxfire" by the ancients), and the
1920 example is of "ignis lambens" (unless Texans are in the habit of putting
rotting wood between the ears of their horses).
Marsh gas is the most mysterious form of foxfire. It moves about as though
alive, and is thus productive of many fantastical tales in Japan and China.
In Vol. IV.1 of *Science and Civilisation in China,* Joseph Needham says:
"Let us return to the classification of Li Shih-Chen in 1596. He was baffled
by the marsh-lights or ignis fatuus, but so are the most modern
investigators, and we are still not sure whether to ascribe the famous
"will-o'-the wisp" to burning methane, spontaneously inflammable
organo-metallic compounds, phosphine (phosphorus trihydride) or alkyl
phosphides, or to electrical discharges. "
This leads to my first question. Have any satisfactory explanations of marsh
gas been offered since Needham wrote these lines in 1962?
In pre-modern times, the "will-o'-the wisp" was frequently observed near
graveyards, execution grounds, and old battlefields where the dead were not
properly buried; thus it was associated with the departed soul of a person
excluded from heaven. How old is this belief? Is it restricted to "popular
superstition," or did learned philosophers of ancient times also accept it?
To what extent does it inform the idea of a "soul" in the Graeco-Roman world?
In other words, who are the "fools" refered to by the New Latin term, "ignis
fatuus"? The writers of ancient Greek and Latin?
Viz: John Swan (Speculum Mundi, Cambridge, 1635): "the much terrified,
ignorant, and superstitious people may see their own errours in that they
have deemed these lights to be walking spirits; or (as the silly ones amongst
the Papists beleeve) they can be nothing else but the souls of such as go to
Purgatorie, and the like. In all which they are much deluded: For souls
departed (Eccles. 9.5,6) cannot appeare again: ..."
In this case, the "fools" are Catholics, the "wise" are Protestants, and the
proof is a verse from the Hebrew Scriptures about the disposition of souls
The case of foxfire/ignis fatuus must be unique for, unlike the many ancient
beliefs that tenaciously continue to the present day inspite of many
successful counterarguments, this superstition seems to have died without a
whimper. I note also that modern dictionaries of folklore, mythology,
religion, and the history of science are extremely unhelpful in documenting
its demise or even its existence. For instance, E. Newton Harvey's 600-page
*History of Luminenscence* (1952) contains a mere 9 paragraphs on ignis
fatuus (he's mostly interested in fireflies and other types of
If anyone knows more information about this phenomenon, and the history of
its folkloristic and scientific explanations, please contact me.
David Olson (Dadad...@aol.com)
P. S. For the benefit of non-native English readers, I offer the following
"translations": French (feu follet, flammerole, furolles); French-Canadian
(feu folette), German (Irrwisch, Irrlicht), Japanese (kitsunebi, hitodama),
Chinese (the character now used for the element "phosphorus"), Danish