Accordingly, the task is to refute skepticism by demonstrating the invalidity of its own premisses.57 In“Botanisten och filosofen”,Hägerström sought to achieve three objectives: f i r st, the refutation of subjectivism, to be more precise subjectivistic epistemology (a refutation accomplished by the demonstration of the skeptical, nihilistic consequences following from subjectivism, thus arguing that any epistemology based upon subjectivism is epistemologically counterproductive, therefore to be abandoned). second, the refutation of pure empiricism (a refutation completed by showing that pure empiricism does not rest on purely empirical foundations, therefore to be revised). th i rd, the establishment of a foundation for an empirical science based neither upon pure empiricism nor on subjectivism (thereby avoiding the problems connected to the empiricistic, realistic and subjectivistic, idealistic positions respectively). Hägerström’s solution: the objectivity of knowledge is based upon reality’s own self-identity.58 Hägerström’s idea is that the self-identity of reality itself constitutes the basis of logic, as it is only by means of the principle of identity that cognitive acts gain theoretical meaning. In addition, empirical sciences rest in general upon the principle of identity as their primary premiss, and rest upon this principle as both a fundamental law of thought as well as an ontological assumption. In either case, the principle affords certainty, objectivity, and reality to our sensations and to the knowledge inferred from them, because it is only from this premiss that the primary supporting principles of empirical science can be deduced validly. One supporting principle is the rep a r t i i i , c h a p t e r 2 186 2 . 3. 2 thre e obj ect ive s of “botani sten och f i losofen” 57 Cf. ibid., pp. 50-51. 58 Ibid., p. 107.