Eric Kandel on Sigmund Freud

“The idea that different aspects of visual perception might be handled in separate areas of the brain was predicted by Freud... when he proposed that the inability of certain patients to recognize certain features of the visual world was due not to a sensory deficit, but to a cortical defect that affected their ability to combine aspects of vision into a meaningful pattern. These defects, which Freud called agnosias (loss of knowledge), can be quite specific.”

“The third great revolution, the Freudian revolution of Vienna 1900, revealed that we do not consciously control our own actions but are instead driven by unconscious motives. This... later led to the idea that human creativity... stems from conscious access to underlying, unconscious forces.”

“The realization that our mental functioning is largely irrational was arrived at by several thinkers at the same time, including Friedrich Nietzsche... Freud, who was much influenced by both Darwin and Nietzsche... was its most profound and articulate exponent. ...Schnitzler, Klimpt, Kokoschka, and Schiele also discovered and explored new aspects of our unconscious mental life. They understood women better than Freud... and they saw more clearly than Freud the importance of an infant's bonding to its mother. They even realized the significance of the aggressive instinct earlier than Freud did. ...Plato discussed unconscious knowledge ...pointing out that much of our knowledge is inherent in the psyche in latent form. ...Hermann von Helmholtz... advanced the idea that the unconscious plays a critical role in human visual perception.”