Thought experiments have played a central and significant role across a broad spectrum of philosophy and science, clarifying and solving complicated puzzles, problems and ideas in the "laboratory of the mind". This book offers a unique capsule history, inviting readers to participate actively in a surprisingly powerful and fruitful tradition. Vivid examples from this fascinating history make up the heart of the book, including Newton"s Bucket, Lucretius" Spear, Salvatius’ Ship, Plato"s Cave, and of course Wittgenstein"s Beetle. Each experiment is followed by a discussion offering possible inferences and consequences. In the final section, Cohen examines the method of thought experimentation suggesting key points for those wishing to harness its power for new explorations.