"If a tree falls..."

[Benjamin Zimmer]

On Wed, 11 May 2005 15:02:33 -0400, Stephen Goranson <goranson at DUKE.EDU>
wrote:

>Though I don't have a copy at hand, it probably appears in Bishop
>Berkeley's A Treatise Concerning the Principles of Human Knowledge
>(1710).

The general philosophical question was raised in Berkeley's _Treatise_,
but he didn't say anything about the sound of falling trees:

-----
http://eserver.org/18th/berkeley.txt
But, say you, surely there is nothing easier than for me to imagine trees,
for instance, in a park, or books existing in a closet, and nobody by to
perceive them.
...
The objects of sense exist only when they are perceived; the trees
therefore are in the garden, or the chairs in the parlour, no longer than
while there is somebody by to perceive them.
-----

It was only much later that the more familiar phrasing was ascribed to
Berkeley:

-----
Bishop Berkeley, by Wm. Lyon Phelps
_Washington Post_, Apr 9, 1935, p. 9
Berkeley's philosophy brings up that fascinating question which can never
be answered -- If a tree falls in a forest and there is no one to hear it,
does it make a sound?
-----

The earliest versions of the question that I can find are from the 1880s,
when at least two magazine readers sought an answer to the conundrum (with
the tree on an island rather than in a forest):

-----
_The Chautauquan_, Vol. 3, Iss. 9, Jun 1883, p. 543
Q. If a tree were to fall on an island where there were no human beings
would there be any sound?
A. No. Sound is the sensation excited in the ear when the air or other
medium is set in motion.
-----
_Scientific American_, Apr 5, 1884, p. 218
S.A.H. asks: If a tree were to fall on an uninhabited island, would there
be any sound?
A. Sound is vibration, transmitted to our senses through the mechanism of
the ear, and recognized as sound only at our nerve centers. The falling of
the tree or any other disturbance will produce vibration of the air. If
there be no ears to hear, there will be no sound.
-----

Interestingly, _Scientific American_ gave the opposite answer some years
later!

-----
_Scientific American_, Jul 8, 1905, p. 34
G.F. says: 1. Is there any sound when there is no ear to hear it? For
instance, if a tree were to fall and there were no living thing within
hearing, would there be any sound? Please explain fully.
A. There may be _sound_ when there is no ear to hear it, and the fall of a
tree would produce exactly the same noise, whether or not there be any one
near at hand. What we call "sound" consists in reality of pulsations or
wave vibrations in the air or whatever medium the sound traverses.
-----


--Ben Zimmer