HUME. 227 experience of the same group of qualities (whenever I see sugar, I do the same thiitg, that is, I combine the qualities white color, sweet taste, hardness, etc., with one another), or the impression of a uniform combination of ideas. The idea of substance becomes erroneous through the fact that we refer it not to the inner activity of representation, to which it rightly belongs, but to the external group of quali- ties, and make it a real, permanent substratum for the latter. Mental substances disappear along with material substances. The soul or mind is, in reality, nothing more than the sum of our inner states, a collection of ideas which flow on in a continuous and regular stream ; it is like a stage, across which feelings, perceptions, thoughts, and volitions are passing while it does not itself come into sight. A permanent self or ego, as a substratum of ideas, is not per- ceived ; there is no invariable, permanent impression. That which leads to the assumption of personal identity is only the frequent repetition of similar trains of ideas, and the gradual succession of our ideas, which is easily confused with constancy. Thus robbed of its substantiality, the soul has no further claims to immateriality and immortality, and suicide ceases to be a crime.* Is Hume roundly to be called a skeptic ?t He neva impugned the validity of mathematical reasonings, nor experimental truths concerning matters of fact ; in regard to the former his thought is rationalistic, in regard to the latter it is empirical or, more accurately, sensationalistic. His attitude toward the empirical sciences of nature and of mind
- Cf. the essays on Suicide and the Immartality of the Soul, 1783, whose
authorship by Hume, however, is not absolutely established [cf. Green and Grose, as above, p. 221. note first. — Tr.] f In the Essay, Hume describes his own standpoint as mitigated or academ' ical skepticism in antithesis to the Cartesian, which from doubt and through doubt hopes to reach the indubitable, and to the excessive skepticism of Pyr- rhonism, which cripples the impulse to inquiry. This moderate skepticism asks us only, after resisting the tendency to unreflecting conclusions, to make a duty of deliberation and caution in judging, and to restrain inquiry within those fields which are accessible to our knowledge, i. e., the fields of mathematics and empirical fact. In the Treatise Hume had favored a sharper skepticism and extended his doubt more widely, <f.^. .even to the trustworthiness of geometry. Cf. on this point Ed. Grimm, Zur Geschichte des ErkenntnissprobUms, 1890,
