So that if we examine the case of a man whose connection with the external world is well known, where the time between the action and its examination is great, and where the causes of the action are most accessible, we get the conception of a maximum of inevitability and a minimum of free will.
His chief work appeared in 1713, under the title Clavis Universalis, or a New Inquiry after Truth, being a Demonstration of the NonExistence or Impossibility of an External World 1 (printed privately, Edinburgh, 1836, and reprinted in Metaphysical Tracts, 1837, edited by Sam.
It is equally opposed to the doctrine which represents the subject itself and its state and judgments as the single immediate datum of consciousness, and all else, whether the objects of an external world or person other than the individual subject whose states are known to itself, as having a merely problematic existence resting upon analogy or other process of indirect inference.
All that we know of the external world of nature is only a certain relation of the forces of nature to inevitability, or of the essence of life to the laws of reason.
Some valuable but isolated facts and theorems had been previously discovered and proved, but it was he who first clearly grasped the idea of force as a mechanical agent, and extended to the external world the conception of the invariability of the relation between cause and effect.
The native attitude of consciousness towards existence is reliance on the evidence of the senses; but a little reflection is sufficient to show that the reality attributed to the external world is as much due to intellectual conceptions as to the senses, and that these conceptions elude us when we try to fix them.
Hence the attempts to train its growing manhood in clerically regulated boarding-schools and to keep it shut out from the external world in clerical seminaries, even in places where there are universities.
He interprets the external world to be the common basis of physical and psychical phenomena.
The first consideration is the clearness of our perception of the man's relation to the external world and the greater or lesser clearness of our understanding of the definite position occupied by the man in relation to everything coexisting with him.
It was in seeking to close up the fissure in his system represented by this dualism that his successors succeeded only in adding weakness to weakness by reducing the principle of sufficient reason to that of formal identity (see Wolff) and representing all thought as in essence analytic. From this it immediately followed that, so far as the connexion of our experiences of the external world does not show itself irreducible to that of formal identity, it must remain unintelligible.