According to Hegel it is one of the merits of Kant to have distinguished between external and internal purposiveness as the latter is the concept of life. Life or organic nature is the precondition of mind and self-consciousness. For Hegel the logical form of life is the concept which explicates the fundamental rational structure of reality and therefore is the main object of philosophy. The inorganic nature by contrast which is the object of physics or mechanics is only a secondary phenomenon and not a reality in the strict sense as it has no unity and is therefore not self-sustaining. In opposition to Hegel Hermann Cohen claims that it is the mathematical science of nature which is the primary object of philosophy and criticizes the post-Kantian idealists who believed it to be the task of philosophy to create a science of nature on the ground of metaphysical principles. The consequence of founding reality on the principle of selfconsciousness is subjectivism and psychologism. But the foundation of science is experience. Accordingly in opposition to Hegel he agrees with Kant that the idea of purpose can be used as a constitutive principle in ethics but has only a regulative function in science, that means it is only a methodological principle of science which serves to explain certain phenomena in nature which would be otherwise inexplicable without allowing thereby to attribute purposiveness to nature itself. This raises the question how the methodological principles of physics and biology are related and more importantly the question, which Kant was unable to solve, how the experience of these special phenomena of purposiveness of nature can be accounted for as they cannot be supposed to be our subjective constructions. Consequently, reality or the object of experience cannot be identified with the object of physics. Cohen formulates this problem of the conception of reality as the problem of the conception of individuality or of the unity of the object of experience, because the object of physics are laws and not singular individual objects. But reality is ultimately supposed to consist in singular objects. Although physics construct ideal singular objects, points in time and space, these ideal objects cannot be supposed to be the real objects of experience. The individual must be supposed to have unity and therefore must be conceived to be self-determined. Cohen insists on the independence of the methodological principles of physics but gives no answer to the question how physics and biology can be reconciled in a coherent conception of reality. Closely connected with this question is the logic of induction as induction is defined as the inference from the individual to the universal. In this project Hegel's and Cohen's conception of reality will be analyzed with reference to the methodological principles of science (mechanics and teleology) and the problem of the logic of induction.