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In Vienna, where did Kurt Gödel Study?
At the age of 18, Gödel joined his brother in Vienna and entered the University of Vienna.
What year did Kurt Gödel start studying at the University of Vienna?
What was Kurt Gödel's major, or field of study?
Although initially intending to study theoretical physics, Kurt Gödel also attended courses on mathematics and philosophy.
Did Kurt Gödel change to another field of study?
During this time, Kurt Gödel adopted mathematical realism. Gödel then studied number theory. According to Gödel, mathematical logic was a science, which contains the ideas and principles underlying all sciences.“

Question: when did he graduate?
Self-contained rewrite: when did Kurt graduate from the University of Vienna?