Task: Text Simplification
Input (English): The concept for which Pavlov is famous is the " conditioned reflex " ( or in his own words the " conditional reflex " ) he developed jointly with his assistant Ivan Filippovitch Tolochinov in 1901 .
Output (English): The concept for which Pavlov is famous is the " conditioned reflex " he developed with his assistant Ivan Tolochinov in 1901 .