The sky in October looks much higher than that in September. That's because there are less clouds up there in October than in September. Since the middle of this August, we've got typhoons almost every weekend in Japan, and that makes me feel as if it rained every day. But it's a beautiful day today. The sun is shining brightly and there are no dark clouds up in the sky. I happened to understand why the sky looks much higher than those in previous months.
In the ancient China, when the autumn came, they needed to prepare to defend themselves from invaders, who would come from Mongolia and central Asia, mounting on strong horses. The awful outsiders would come to plunder the crops from Chinese farmers. Thus they would have been alert to the attacks from invaders as well as would have been grateful for the harvest under the autumn sky.