The butterfly effect is a metaphor that encapsulates the concept of sensitive dependence on initial conditions in chaos theory; namely that small differences in the initial condition of a dynamical system may produce large variations in the long term behavior of the system.
In human behavior, one can certainly see how small changes could render behavior, or another complex system, extremely unpredictable. Small actions or experiences stored in the unconscious mind, could certainly affect a person’s behavior in unexpected ways.