不同质的矛盾，只有用不同质的方法才能解决。 - Mao Zedong

Before it explodes, a bomb is a single entity in which opposites coexist in given conditions. The explosion takes place only when a new condition, ignition, is present. An analogous situation arises in all those natural phenomena which finally assume the form of open conflict to resolve old contradictions and produce new things.

Policy is the starting-point of all the practical actions of a revolutionary party and manifests itself in the process and the end-result of that party’s actions. A revolutionary party is carrying out a policy whenever it takes any action. If it is not carrying out a correct policy; it is carrying out a wrong policy; if it is not carrying out a given policy consciously, it is doing so blindly. What we call experience is the process and the end-result of carrying out a policy. Only through the practice of the people, that is, through experience, can we verify whether a policy is correct or wrong and determine to what extent it is correct or wrong. But people’s practice, especially the practice of a revolutionary party and the revolutionary masses, cannot but be bound up with one policy or another. Therefore, before any action is taken, we must explain the policy, which we have formulated in the light of the given circumstances, to Party members and to the masses. Otherwise, Party members and the masses will depart from the guidance of our policy, act blindly and carry out a wrong policy.

Over a long period we have developed this concept for the struggle against the enemy: strategically we should despise all our enemies, but tactically we should take them all seriously. This also means that we must despise the enemy with respect to the whole, but that we must take him seriously with respect to each and every concrete question. If we do not despise the enemy with respect to the whole, we shall be committing the error of opportunism. Marx and Engels were only two individuals, and yet in those early days they already declared that capitalism would be overthrown throughout the world. But in dealing with concrete problems and particular enemies we shall be committing the error of adventurism unless we take them seriously. In war, battles can only be fought one by one and the enemy forces can only be destroyed one by one. Factories can only be built one by one. The peasants can only plow the land plot by plot. The same is even true of eating a meal. Strategically, we take the eating of a meal lightly—we know we can finish it. But actually we eat it mouthful by mouthful. It is impossible to swallow an entire banquet in one gulp. This is known as a piecemeal solution. In military parlance, it is called wiping out the enemy forces one by one.