Brahma Knowledge, by L. D. Barnett, , at sacred-texts.com
§ 20. Karma.—The propelling force which conducts the Soul with its potential functions through endless incarnations as man, god, beast, or vegetable, is the karmāśraya, the substrate of its karma or works. By "work" is understood not only every act of will, and of body in obedience to will, but also every act of ideation in which the subject of thought posits a non-self in opposition to itself, for in this false duality begins the Will, desire, attachment of the soul to its fetters of finitude, and therewith moral blindness. Every such act transforms itself into a positive force acting upon the soul, and demanding a corresponding requital of good for good and evil for evil in future experiences; and the sum of these forces at the end of each life determines the form of birth in the next incarnation. 1
46:1 See especially B.A. III. ii. 13 (probably the earliest assertion of this theory as a solution of the problem of moral character), IV. iv. 2-6, Ch. III. xiv. 1, Śankara on Brahma-sūtra, III, iv. 11, IV. ii, 6, and above, § 6, below, § 24.