The intellectual and cultural movement known as the French Enlightenment spawned a complex of intellectual activities and novel concepts that positively impacted on the genesis and development of special education. Educational pioneers incorporated the essential tenets of l'esprit philosophique in work with sensorily deprived, mentally retarded, and emotionally disturbed children. In doing so, they altered societal perceptions of the aptitudes of handicapped individuals, devised training methods that are still used today, and imbued special education with a dynamic arid intense spirit of hope and optimism.