Aenesidemus (book)

Aenesidemus is a German book published anonymously by Professor Gottlob Ernst Schulze of Helmstedt in 1792. Schulze attempted to refute the principles that Karl Leonhard Reinhold established in support of Immanuel Kant's Critique of Pure Reason (1781). The title is a reference to Aenesidemus, an ancient Greek skeptical philosopher. Its complete title, in English translation, was Aenesidemus or Concerning the Foundations of the Philosophy of the Elements Issued by Professor Reinhold in Jena Together with a Defense of Skepticism against the Pretensions of the Critique of Reason (German: Aenesidemus oder über die Fundamente der von dem Herrn Professor Reinhold in Jena gelieferten Elementar-Philosophie. Nebst einer Vertheidigung des Skepticismus gegen die Anmassungen der Vernunftkritik).

The book was supposed to be a written correspondence between Hermias (Greek: "a follower of Hermes"), who believes in the Kantian critical philosophy, and Aenesidemus (Greek: "he who praises the people"), who is skeptical about that philosophy. The skepticism of David Hume's skepticism about induction, according to this book, was not disproved by Kant. As Hume had asserted, the existence of causality, the soul, or the thing-in-itself cannot be proved.

Philosophy cannot establish the existence or non-existence of the thing-in-itself. By establishing general principles, we can't know the limits of our ability to know. Progressive development, however, can approach complete knowledge.

No skeptic can doubt the reality and certainty of mental representations and mental events that are immediately given through consciousness.

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