Working largely in isolation from mainstream psychologists in Byelorussia, Vygotsky developed theories of learning similar to those of Piaget. His works emphasize the socially transmitted knowledge of the teacher and the active engagement of the child in the learning process; they are free of doctrinaire Marxist dogma, and sought a reconciliation between different schools of psychology. His works include Thought and Language and The Crisis of Psychology; they were only published posthumously, shortly thereafter suppressed, and known only in the West after 1958.