German Idealism

German idealism was a speculative philosophical movement that emerged in Germany in the late 18th and early 19th centuries. It began as a reaction to Immanuel Kant's Critique of Pure Reason and was closely linked with both Romanticism and the revolutionary politics of the Enlightenment. The most notable thinkers in the movement were Johann Gottlieb Fichte, Friedrich Schelling and Georg Wilhelm Friedrich Hegel, while Friedrich Heinrich Jacobi, Gottlob Ernst Schulze, Karl Leonhard Reinhold and Friedrich Schleiermacher also made major contributions.

The word "idealism" has more than one meaning. The philosophical meaning of idealism here is that the properties we discover in objects depend on the way that those objects appear to us, as perceiving subjects, and not something they possess "in themselves", apart from our experience of them. The very notion of a "thing in itself" should be understood as an option of a set of functions for an operating mind, such that we consider something that appears without respect to the specific manner in which it appears: correlating more to something like "idea-ism" than the common notion of idealism. The question of what properties a thing might have "independently of the mind" is thus unknowable and a moot point within the idealist tradition.

Kant's work purported to bridge the two dominant philosophical schools in the 18th century: 1) rationalism, which held that knowledge could be attained by reason alone a priori (prior to experience), and 2) empiricism, which held that knowledge could be arrived at only through the senses a posteriori (after experience). Kant's solution was to propose that while we can know, via sensory experience, particular facts about the world (which he termed phenomena), we cannot know the form they must take prior to any experience (which he called noumena). That is, we cannot know what objects we will encounter, but we can know how we will encounter them. Kant called his mode of philosophising "critical philosophy", in that it was supposedly less concerned with setting out positive doctrine than with critiquing the limits to the theories we can set out. The conclusion he presented, as above, he called "transcendental idealism". This distinguished it from classical idealism and subjective idealism such as George Berkeley's, which held that external objects have actual being or real existence only when they are perceived by an observer. Kant said that there are things-in-themselves, noumena, that is, things that exist other than being merely sensations and ideas in our minds. Kant held in the Critique of Pure Reason that the world of appearances (phenomena) is empirically real and transcendentally ideal. The mind plays a central role in influencing the way that the world is experienced: we perceive phenomena through time, space and the categories of the understanding. It is this notion that was taken to heart by Kant's philosophical successors.

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