443. Thus, the thought-world of living beings is filled with multifarious and highly varied thought-climates in the same way as their physical world is filled with different meteorological climates. These climates are not always favourable for Man, indeed, to a large extent they are actually harmful, for in some places it is too cold, in others too hot, some areas are too damp and others too dry, some places conduce fever and others cyclones, floods and earthquakes, so people have always had a struggle; and just in the same way thought-climates are not always to the direct advantage of the I's. And likewise, as people have had to overcome the harmful phenomena of the physical climates by building houses, installing heating systems, dressing in clothing, creating irrigation plants, constructing dams, dykes and drains, making purely physical power-plants, inventing antidotes against tropical diseases, ordinary illnesses and so on, thereby being able to inhabit the whole globe, so to speak, or at least be able to journey around it anywhere from pole to pole, then people must also take up the fight against life-threatening thought-climates and learn to subdue them, if they want to reach an existence which is raised above an animal's primitive level of consciousness.
      It is an incontestable fact shown by the mental chaos in terrestrial man's course of life, especially now in our time, that thought-climates in an uncontrolled condition are immeasurably dangerous and also that mankind, to an exceptionally large extent, is still quite unaware of it.
      Although people are already well informed about meteorological climates and understand how to protect themselves in this respect – for we never see a polar expedition clothed in tropical attire or a tropical expedition fitted out with furs – yet they are entirely at a loss when it is a question of mental climates. In this case people refuse at times to clothe themselves, rushing out in the cold, stark naked and freezing to death and at other times they are in a "tropical climate" dressed in overcoats and furs, gasping to death from lack of coolness. This indicates that terrestrial man sometimes fills his mind with thought-material which is pure poison, having a fatal, injurious or destructive effect on himself, that is to say on his mind, and in this way his physical as well as his mental faculties and behaviour are undermined. That mankind is not in contact with mental climates is shown by the many hospitals for the mentally ill and handicapped that are being built the world over. In reality insanity or mental illness is caused by using far too large an amount of poisonous thought-material and by far too feeble a control over the penetration of these materials into the consciousness; consequently there is far too weak a protection against them.
      Just as the physical climate in certain parts of the world is directly destructive for human existence if it is not resisted by means of people's experience or wisdom with counter-measures or protective arrangements, in the same way thought-climates are in many areas absolutely destructive and ruinous for people's natural behaviour if they are not countered by protective measures. Already at an early stage terrestrial people began to be aware of this fact. This is shown by all the many more or less correct, or supposedly correct, counter-measures people have long ago begun to demonstrate and are still attempting to develop.