436. (11) In both worlds these two atmospheres meet, but do not combine together. By both worlds we mean the spiritual world and the natural world. In the spiritual world these atmospheres meet in the world of spirits, because this is intermediate between heaven and hell. In the natural world, however, they meet on the rational plane in a person, which likewise is intermediate between heaven and hell; for the marriage of good and truth flows into it from above, and the connubial alliance of evil and falsity from below. So it is that human rationality can turn itself in either direction and receive an influx. If it turns in the direction of good, it receives an influx from above, and then the person's rationality is formed more and more for the reception of heaven. But if it turns in the direction of evil, it receives an influx from below, and then his rationality is formed more and more for the reception of hell. [2] These two atmospheres do not combine because they are opposed, and things that are opposed do not act upon each other except as enemies, one of which is blazing with deadly hatred and attacks the other in rage, while the other is without any hatred but only possesses a zeal to protect itself. It is apparent from this that these two atmospheres merely meet but do not combine together. The middle ground which they create between them consists on the one hand of evil without falsity and of falsity without evil, and on the other hand of good without truth and of truth without good. These two can indeed border each other, but they cannot combine together.