the first objection that concerns me here. Stumpf gives as an example,
under his first objection, the singing of a series of tones, C, G, E,
F. We have here the muscle sensations from the larynx, and the series
of the tone-sensations which are, Stumpf claims, reversed when the
muscle-sensations are reversed, etc. According to Stumpf, these are
all the elements that are required by Bain, and yet we have no
perception of space thereby. Henri[22] has pointed out two objections
to Stumpf's criticism of Bain's theory. He says that Bain assumes,
what Stumpf does not recognize, that the muscle sensations must
contain three elements--resistance, time, and velocity--before they
can lead to space perceptions. These three elements are not to be
found in the muscle sensations of the larynx as we find them in the
sensations that come from the eye or arm muscles. In addition to this,
Henri claims that Bain's theory demands a still further condition. If
we wish to touch two objects, _A_ and _B_, with the same member, we
can get a spatial experience from the process only if we insert
between the touching of _A_ and the touching of _B_ a continual
series of tactual sensations. In Stumpf's instance of the singing of
tones, this has been overlooked. We can go from the tone C to the tone
F without inserting between the two a continuous series of musical
sensations.

[22] Henri, V., 'Ueber d. Raumwahrnehmungen d. Tastsinnes,'
Berlin, 1898, S. 190.

I think that all such objections to the genetic space theories are
avoided by formulating a theory in the manner in which I have just
stated. When one says that there must be an outer activity producing a
displacement of sensation, and then an inner activity retaining that
sensation, it is plain that the singing of a series of tones ascending