On the principles and method of a practical science of mind : a reply to a criticism / by Thomas Laycock.

  • Thomas Laycock
Date:
1862
Catalogue details

Licence: Public Domain Mark

Credit: On the principles and method of a practical science of mind : a reply to a criticism / by Thomas Laycock. Source: Wellcome Collection.

Provider: This material has been provided by The University of Glasgow Library. The original may be consulted at The University of Glasgow Library.

    17/28 (page 15)
    svstem is equally maintained by a similar series of self-adjustments; while these have been so clearly manifested in animals and plants, as to have originated the medical theory of a vis medlcalrix and con- servatrix. That a knowledge of the latter and of the laws by which tliey are brought about, is necessary to a rational system of practice of meihcine is so obvious, that the tendency of safe modern ])ractice as it was of the ancient, is to guide rather than disturb the natural processes. Another illustration of this kind is afforded by Avliat has been termed the balance of animated nature, in which there are such adjustments as to the reproduction and destruction of animals and plants of various genera and species, and such a supply of what is necessary to continued and healtliy existence secured, that a stable and harmonious whole residts. Of late years, this principle has been applied to legislation, and the old meddlesome interference with the self-adjusting forces of society deprecated, like meddlesome physic ; because their free operation judiciously guided, has been found to be the surest guarantee for national health and stability. I mention these illustrations as constituting the most decisive proofs of both the truth and practical value (which must go together,) of my general principle. Just as the law of gravity a])plies equally to a grain of sand as to the countless masses of the universe, so this general law upon which I rest my system of mental science, applies equally to tlie needs of an infusorial animalcule, as of civilized society, and regulates the adjustments of the universe as surely as those of the smallest organism. There is one other point to be borne in mind as to this law (and which is obviously suggested by the preceding considerations), viz., that the forces of nature acting thus under the influence of a law of design or directing force, do not attain one end exclusively by any one series of changes, but many. Thus for example, the deposit of fat in arctic marine animals probably subserves other purposes in the economy, and so maintains them in life and in health, than that obvious one of keeping the body at a temperature of 96*^-100° I'ahr. These purposes must be ascertained by experiment and observa- tion ; a priori speculation can only develop theories at the best, to be confirmed by research before they can be accepted as a true statement of facts. In other words, before we can say what ends are attained, they must be discovered. This teleiotic or directive force being thus in my system, the proxi- mate cause of the vital or teleorganic changes which go on in the encephalon (as the organ of consciousness,) in common with all other living tissues, it is necessary to determine its general laws and their modifications, accordingly as various functions are required to be per- formed by either the encephahc or other tissues. Now the first law is that of incessant change in the tissue; no change whatever arises in the consciousness, without a corresponding change or series