Zettel

Zettel  is a collection of assorted remarks by Ludwig Wittgenstein, first published in 1967. It contains several discussions of philosophical psychology and of the tendency in philosophy to try for a synoptic view of phenomena. Analyzed subjects include sense, meaning, thinking while speaking, behavior, pretense, imagination, infinity, rule following, imagery, memory, negation, contradiction, calculation, mathematical proof, epistemology, doubt, consciousness, mental states, and sensations.