Activity theory
Activity theory (AT; ) is an umbrella term for a line of eclectic social sciences theories and research with its roots in the Soviet psychological activity theory pioneered by Lev Vygotsky , Alexei Leont'ev and Sergei Rubinstein. These scholars sought to understand human activities as systemic and socially situated phenomena and to go beyond paradigms of reflexology (the teaching of Vladimir Bekhterev and his followers) and classical conditioning (the teaching of Ivan Pavlov and his school), psychoanalysis and behaviorism. It became one of the major psychological approaches in the former USSR, being widely used in both theoretical and applied psychology, and in education, professional training, ergonomics, social psychology and work psychology.
Ballet d'action
Although the French choreographer Jean-Georges Noverre is often credited with the original ideas and definitions of what he termed “ballet en action”, there were various other influences that contributed to the development of the genre. While Noverre’s 'Letter 1' provides a clear outline of his ideas of ballet d’action, he was not the first nor the last to develop a theory of a ballet in action.