An overall comprehension of the relationship between universality and particularity of contradiction

In the current textbooks on the philosophy of Marxism, when talking about the concept of contradiction, only the universality of its existence is illustrated, leaving the universality of its property undiscussed. However, in 'On Contradiction' written by Mao Ze-dong, both the universality of the existence of contradiction and that of the property of contradiction are discussed. The universality of contradiction should be comprehended in both aspects. Only in this way can we have an overall and correct comprehension that the relationship between universality and peculiarity of contradiction is the relationship between generality and individuality.Hence the methodology significance of it can be understood properly.