Returning from travels in war-torn Europe, Rudolf Steiner gives a stark impression of the disastrous conditions of the time, encouraging deeper esoteric work as a counter to the world-situation. Speaking under the broad theme of human development in the light of anthroposophy, he analyses the gulf between contemporary culture and science - which he says are characterized by 'narrow-mindedness, philistinism and ineptitude' - and a scientific approach to the spirit. At the same time, Steiner is clear-sighted about the shortcomings of his followers, mentioning past failures and a continuing tendency towards sectarianism and dogmatic judgements. Rudolf Steiner discusses how we experience a state of separateness with the world through our physical form, whilst our aura - or soul-spiritual being - is already living actively in cosmic surroundings. A conscious crossing of the threshold into the spiritual world is urgent and necessary today, although Steiner warns of the dangers inherent in certain eastern and western approaches. The tendency of initiates of the Orient is to abandon the human race, whilst the American impulse is immersed too strongly in physical, bodily nature. And a potential demonic influence works through technology. However, a spiritual-scientific path of knowledge and development can allow us to navigate through these challenges. Other themes featured include: the threefold Sun Mystery of ancient times; the Mystery of Christ Jesus and the threefold being of man; the human limbs as thoughts of the higher hierarchies; the loss of the spiritual knowledge of the old Mysteries; the gulf between idealism and realism; the formation of language from Cosmic Intelligence; the Pythagorean School and the mendacity of the world at that time; the disintegration of words after death; the twelve senses; the spiritual impact of old people's death on the physical Earth; and the impulse of socialism. The wealth of spiritual thoughts and knowledge presented in these lectures remain as relevant today as they did when the they were first delivered.