The Study of the Philosophy of Science
G. J. Whitrow
Advanced Grammar in Use with Answers
Martin Hewings
Entertaining Mathematical Puzzles
Martin Gardner
Das Wahre, Schöne, Gute: Geist und Kultur im 3. Jahrtausend
Kenneth E. Wilber
Early Greek Philosophy
Various
Philosophy of Mind: 50 Puzzles, Paradoxes, and Thought Experiments
Torin Alter & Robert J. Howell & Amy Kind