Plato saw our main problem as being the physical body and its weakness; for Marx it was unjust economic systems; for Freud it was inner unconscious conflicts between desire and conscience; for Sartre it was not realizing we are completely free since there are no objective values; for B.F. Skinner it was not realizing we are completely determined by our environment; and for Konrad Lorenz it was our innate aggression because of our evolutionary past.
