When water in a kettle hangs over fire, the two elements stand in relation and thus generate energy (cf. the production of steam). But the resulting tension demands caution. If the water boils over, the fire is extinguished an its energy is lost. If the heat is too great, the water evaporates into the air. These elements here brought in to relation and thus generating energy are by nature hostile to each other. Only the most extreme caution can prevent damage. In life too there are junctures when all forces are in balance and work in harmony, so that everything seems to be in the best of order. In such times only the sage recognizes the moments that bode danger and knows how to banish it by means of timely precautions.