Dr. Bose found, in the plant as well as in the animal, "a similar series
of excitatory effects, whether these be exhibited mechanically or
electrically. Both alike are responsive, and similarly responsive, to
all the diverse forms of stimulus that impinge upon them. We ascend, in
the one case as in the other, from the simplicities of the isotropic to
the complexities of the anisotropic; and the laws of these isotropic and
anisotropic responses are the same in both. The responsive peculiarities
of epidermis, epithelium, and gland; the response of the digestive
organ, with its phasic alterations; and the excitatory electrical
discharge of an anisotropic plate, are the same in the plant as in the
animal. The plant, like the animal, is a single organic whole, all its
different parts being connected, and their activities co-ordinated, by
the agency of those conducting strands which are known as nerves. As in
the plant nerve, moreover, so also in the animal, stimulation gives rise
to two distinct impulses, exhibiting themselves by two-fold mechanical
and electrical indications of opposite signs.... The dual qualities or
tones known to us in sensation, further, are correspondent with those
two different nervous impulses, of opposite signs, which are occasioned
by stimulation. These two sensory responses--positive and negative,
pleasure and pain--are found to be subject to the same modifications,
under parallel conditions, as the positive and negative mechanical and
electrical indications with which they are associated. And finally,
perhaps, the most significant example for the effect of induced
anisotropy lies in that differential impression made by stimulus on the
sensory surfaces, which remains latent, and capable of revival, as the
memory-image. In this demonstration of continuity, then, it has been
found that the dividing frontiers between Physics, Physiology, and
Psychology have disappeared."[22]