And we have learnt also to expect change as a result of judging atmospheres; after a long period of sunny weather has grown tired and flowers are wilting we easily sense in a build-up of humidity that there will be a tremendous thunderstorm that will render everything fresh and clean again. This is yang becoming old and tired and discharging itself to become young and fresh yin. Yin becoming old and tired can be seen in the long drawn-out winter days suddenly greeting the first sunshine, not quite spring, there is still a chill in the air, but the insects are awakening, flowers beginning to bloom, and this feeling is young and vibrant yang being aroused. The dragon (very yang) indeed begins his ascent in the spring, coming out of winter hibernation. And in the span of a single day the cycle of yin and yang can be witnessed, perhaps the morning will start off dour, the sun swathed in clouds, but by afternoon the clouds have dispersed and the sun is out. As it says in Daodejing 23: 'Gusts of wind do not blow all morning. The downpour will not last all day.'