companies perfect use of our faculties, and pain their impeded use. The philosophy which prevailed after Aristotle was dominated by the Oriental superstition that the forces of this world are divided between the Powers of Good and of Evil. How this superstition seized upon and biased the dogmas of our theologic ancestors until belief in a personal Devil was universal among even the learned in the middle ages, is a matter of undisputed history. Aristotle's doctrine fitted well with this superstition, and his unquestioned authority enforced its universal acceptance. Thus, as late as 1647, we have Descartes, the highest authority of his age, declaring that "All our pleasure is nothing more than the consciousness of some one or other of our perfections." When Science dawned, and began basing mental activities upon correspondent neural processes, nothing was easier or more inevitable than that the doctrine which always had been conceded to express general conditions of welfare and activity should be transferred to general conditions of the nervous system; and that, in general, heighted neural discharge" should be declared to be the basis of pleasure, and the reverse to be the basis of pain. Thus, an early conjecture of Aristotle, fostered by one of the grossest theological superstitions, and transformed, as I shall show, by most uncritical and fallacious physiological assumptions, is the historic origin of what Prof. Baldwin calls "A New Factor in Evolution.3

The origin of the notion having been accounted for independently of any critical regard of the facts, we will now examine it in the light of the facts. We have no means of examining neural discharges directly, or independently of their stimuli, their sensory effects, and their motor results; we have no other means of measuring them, except through analogy with the strength of these. In general it is fundamentally observed that where the stimulus is intense the sensation is intense. Also, muscular reaction is proportional to the stimulus and to the sensation. Every known fact, outside of the phenomina of pain and pleasure in dispute, conforms to the in

Whether it is with reference to Spencer, Bain, Descartes or Aristotle, that this factor is "new," Prof. Baldwin does not state.

ference that the stimulus, the neural discharge, the physic counterpart, and the motor result, rise and fall together. Beginning now with the motor reactions of pain, it is to be observed that they are among the strongest and most violent of which we are capable; the violent struggles that every creature makes to free himself from pain, or that he displays, reflexly, in the convulsions of its torture, are among the most familiar facts known. Again, it is equally well known, that the stimuli which cause pain are the most violent that we encounter; usually it is for that reason that they are detrimental. Also, pain is the strongest and most violent of our sensations. When, therefore, all the evidences alike, from every common source of observation, agree that the neural discharge ought to be strong proportionally as the stimulus, the sensation, and the motor reactions are strong, it would seem that we ought to conclude that the neural discharges of pain are strong.

Surely we ought so to conclude, unless Prof. Baldwin has further evidence to offer. The evidence most likely for him to offer is that pain is characteristic of exhaustion, weakness, disorder and disease. This is the stronghold of the traditional school, and has been the secret of its fallacy from its beginning. Yet, there is not a single one of these phenomena that is not perfectly explained without accepting the tradition, and without any of the violations of fundamental analogies which its acceptance necessitates. This is done upon the basis of specific pain-nerves. Every analogy demands that there should be such nerves. If all other sensations have specific nerves so should pain. They have long been anticipated in physiology. And recently they have been demonstrated with surprisingly wide-founded and abundant evidence ;* quite equal indeed to that for the nerves of touch.

Necessarily the universal distribution of these nerves brings them into close connection with the vaso-motor mechanism. Wherever there is unusual congestion of the blood there is

See article in Brain, p. 1, 1893, and p. 339, 1894, by Dr. Henry Head of University College Hospital, London. Also those by Prof. von Frey in Berichte d. math. phys. classe d. Königl. Sachs. Gesellschaft der Wissenschaft zu Leipzig, 1894, pp. 185 and 283; 1895, p. 166.

likely to be pain. We are not certain what the appropriate form of stimulus is for the pain-nerves, but assuming it to be mechanical pressure, then any unusual stretching or tension, whether in the capillaries or the surrounding tissues, as caused by congestion, or from undue secretion of any of the glands, or from any other disorder, would perfectly explain the attendance of pain. That this should explain the characteristic pains of exhaustion, weakness, disease, and all other abnormal ities, rather than the mere loss of general bodily strength, to which the common tradition more directly attributes them, no scientist should doubt. For, first, there is no evidence that mere weakness, independently of the physiological derangements which are the co-results of its cause, are at all painful. A man may bleed to death, and suffer no pain. Again, a frail invalid may fade away with weakness, and suffer no trace of pain'; indeed, may depart with gladness. Ora sprinter may drop with exhaustion and, perhaps, suffer no pain at all; or if any, none save what is unmistakably due to the abnormal disturbances of circulation already referred to. Secondly, all causes of weakness are likely to produce disorders which, in turn, shall produce disturbances likely to excite the painnerves in the way above indicated. This is so evident that it need not be discussed. Third, when so excited, even during general bodily weakness, there is still every evidence that the pain discharges are characteristically strong above other nervous activities, and relatively so proportionally to the lowering of the general level of strength. It would seem, therefore, that every known phenomena of pain, on the one hand, receives perfect explanation on the basis of pain-nerves, that every analogy demands such nerves, and that finally they have been. conclusively demonstrated. And, on the other hand, it is strikingly manifest that every evidence we possess flatly contradicts the assumption that pain discharges are feeble.

The corresponding assumption that the neural discharge of pleasure is "excessive " equally fails of corroboration when confronted with the facts. Here, again, we can measure the discharge only by its psychic accompaniment, its stimulus, and its motor effect. That pleasures, among psychic states, are charac

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teristically intense, is not true. Again, that intensity of stimulus is not a uniform determinant of pleasure is one of the best known truths of every form of art. And that the motor effects of pleasure are not conspicuous for violence is not less well known. Some of them are violent, no doubt, yet abundance of others are among the most soothing and quieting influences which we experience. The entire field of pleasure therefore -source, centre, and motor discharge-is one endless contradiction of the assumption that its neural discharge is predominately intense, and points even to a new definition of pleasure from that of which the traditional school is possessed. Again, it is the delusive general relationship of pleasure to health, strength and welfare which has ever been the source of error. With health and freshness all functions, undoubtedly, are more vigorous, and those which give pleasure are more active among the rest. Also, in health we are freer of unpleasant disorders. Yet it remains true that the feeblest invalid is often capable of the intensest pleasure, and that the trained athlete may suffer excruciating pain if the dentist but tickle the bare nerve of his tooth with a feather.

Against the "discharge " link, pleasurable or painful, in Mr. Baldwin's "Circular Reaction," it would seem unnecessary to push the sword further. In has absolutely no foundation in fact. Yet, as this is of a class of tradition that dies hard, I will bring yet multiplied objections against it. When a child first brings its finger into contact with a flame it instinctively draws its arm away: a complicated and delicately articulated mechanism has been evolved by nature, and inherited by the child for this purpose. The case is typical, and other examples are innumerable. Now, under Mr. Baldwin's Plan of Evolution, it would have been impossible for such an organized response to pain to have developed. His whole scheme is one wherein "the excess discharges" of pleasure conduce to the development of organized responses to pleasure, and the "restricted discharges" of pain specially prevent the development of organized responses to pain. It is true that Mr. Baldwin expressly declares his "New Factor" to be ontogenic. Still, if so, then pain restrictions must have yet worked from the moment of each creatures

birth to stamp out every provision of the type above cited. Over and above this, every intelligent organization against detrimental forces would be impossible from the moment of birth.

This is no small obstacle to the universal acceptance of Mr. Baldwin's "New Factor," yet the more intimately we approach it the more do the difficulties increase. This time for a bull'seye example we will take a plunge straight at the " pain-pleasure discharge" itself. Mr. Baldwin tells us it is "central "let us now ask to what is it proportional? What gauges its "heightening" or its "restriction?" The pain or the pleasure, of course, Mr. Baldwin answers, since his "New Factor" is a psychic factor. But to which is the pain or pleasure proportionate the incoming sensory nerve current, or the “benefit from the external stimulus?" It is just here that a " tremendous" (to use a favorite word of this enthusiastic writer) stumblingblock arises. Mr. Baldwin tells us with emphasis that the pleasure comes in and by the stimulus. But how and in what manner does the external pleasure-stimulus connect with the centrally rising" heightened discharge"? Plainly it cannot be through the mere intensity of the ordinary incoming sensory nerve-current; for the pleasure is proportional to the benefits from the external stimulus; and these benefits are by no means proportional to the intensity of the stimulus. But, perhaps, Mr. Baldwin conceives-he does not tell us here in the least what he does conceive, though it is an absolutely essential point of some specific kind or mode of neural activity to convey his pleasure-stimulus from the periphery to the centre, and one in no way parallel to the intensity of the external stimulus. If so, then a still greater difficulty now arises to conceive how the "benefit" or the "detriment" from the external event expresses itself through this new mode of communication. We are told that the pleasure is proportional to the amount of the benefit worked by the stimulus, not to its intensity. But just how and when does this "amount" get transformed into this new kind of ingoing pleasure current? Benefit is a "tremendously" abstract affair. Where does it end, and when does it act? The benefit does not happen instantly-when then is its pleasure experienced? How and