Page:Philosophical Review Volume 1.djvu/422

This page has been proofread, but needs to be validated.
406
THE PHILOSOPHICAL REVIEW.
[Vol. I.

as its quale. At times even, as may be experienced, pain becomes so excruciating and dominant as to usurp all other mental content or consciousness. All this seems to show that pain is a separate sensation. No doubt we may, at times, have pains simultaneously with other sensations. I may press my hand so as to feel both pain and touch or pressure. But I may as well, at times, experience a sound and a touch.

That pain has a slower rate of nerve conduction than other sensations can be observed even in health. But particularly is this noticeable in certain pathological conditions. In certain cases of tabes dorsalis, if a cold needle be thrust into the patient's skin, he will feel the touch and cold from a half to two seconds before the pain.

Pain also has a separate path through the spinal cord. In certain pathological conditions of the cord, as those caused by lead poisoning, pain is lost to the lower extremities, while the other senses remain intact. Again, under chloroform, the patient will be extremely sensitive to the slightest touch, yet feel no pain from severe pinching, cutting, tearing, or burning within the same area. On the contrary in certain other pathological states pain remains, while susceptibility to all other sensation is lost. If cocaine or menthol be applied to the skin, or ice to the elbow, we can note the constant order in which touch, pressure, heat, and cold each lapse, leaving pain at the end, by itself, it finally going as the others. Thus pain sometimes stays while all the other senses go, and sometimes goes when the other senses stay, which surely looks as if it were not a quale inseparable from the other senses.

As confirmatory of the separate nature of pain, we now have to add the very important testimony of Goldscheider. He reports having discovered and positively demonstrated isolated specific pain nerves. If this be corroborated, it settles beyond question the specific quality of bodily pains or pain sensations. That the demonstration is correct there seems no reason to doubt. Goldscheider is admittedly the greatest living authority in this particular department, and is excelled by none in pains-taking exactness and reliability. His discovery is in line with