text: Stanley Cavell analyzes this philosopher and "skepticism, morality, and tragedy" in his magnum opus, The Claim of Reason.
full_question: Stanley Cavell analyzes this philosopher and "skepticism, morality, and tragedy" in his magnum opus, The Claim of Reason. This thinker argued that groups of activities do not have one defining commonality, but instead have a set of "family resemblances". This thinker described a shopkeeper who has to look up the word "red", and described builders being told to collect "blocks, pillars, slabs and beams". This creator of language games closed another book with the line, "whereof one cannot speak, thereof one must be silent". For 10 points, name this Austrian philosopher who wrote Philosophical Investigations and the Tractatus Logico-Philosophicus.
first_sentence: Stanley Cavell analyzes this philosopher and "skepticism, morality, and tragedy" in his magnum opus, The Claim of Reason.
raw_answer: Ludwig Wittgenstein [or Ludwig Josef Johann Wittgenstein]