Hartley's theory of the human mind : on the principle of the association of ideas; with essays relating to the subject of it / By Joseph Priestley.

  • Hartley, David, 1705-1757.
Date:
1775
Catalogue details

Licence: Public Domain Mark

Credit: Hartley's theory of the human mind : on the principle of the association of ideas; with essays relating to the subject of it / By Joseph Priestley. Source: Wellcome Collection.

    21/442
    £ S S A Y §. xvu in the particles of the nerves and brain, occafioned by the vigorous vibrations which accompany the fenfe of pain. If it be admitted, as I think it muff be, that, for any thing that yet appears, vibrations in the brain may accompany and be the caufe of all our ideas, there remains only one property of ideas, or rather of the mind relating to them, to which if the do6lrine of vibrations can be fuppofed to correfpond, the w7hole theory will be eflablifhed, and that is the ajfociation of ideas. For it will be feen that this fin- gle property comprehends all the other affe&ions of our ideas, and thereby accounts for all the pheno¬ mena of the human mind, and what we ufually call its different operations, with refpeft to fenfations and ideas of every kind. Now if two different vibrations take place in the brain at the fame time, it cannot be but they will a little alter or modify one another, fo that the par¬ ticles of the medullary fubffance will not vibrate precifely as they would have done if they had taken place feparately; but each of them will vibrate as a&ed upon by two impulfes at the fame time ; and all the particles being a&ed upon in the fame man¬ ner, it neceffarily follows that, if from any caufe whatever, one of thefe vibrations (hall be excited, the other will be excited alfo, fo that the whole flute of the brain will exa&ly refemble what it wTas before; and this feems to correfpond fufficiently to the re- colleftion of one idea by means of another. b I do