4.3 Blind negation of formal logic
At the other extreme is the blind negation of formal logic. Hegel mocked formal logic, "The law of identity is then expressed as 'everything is identical with itself '; Or 'A is A', negative: 'A cannot be both A and non-A at the same time.' Such propositions are not really laws of thought, but only laws of abstract intelligence. The form of this proposition is itself in contradiction. For a proposition must make the distinction between subject and predicate, but this proposition does not do what its form requires of it." "It would be ridiculous if people were to speak according to this law which pretends to be the truth." "Do not think of identity simply as abstract identity, as identity that excludes all differences. This is what distinguishes all bad philosophy from the only philosophy worthy of being called philosophy."[3-4]
Hegel saw that formal logic was not objective, but he did not understand the value of formal logic. In his Philosophical Notes, Lenin several times excerpted Hegel's criticism of the identity of the abstract and the concrete, expressing his approval. In Popular Philosophy, Ai Siqi bluntly declared: "We have long since declared the death of formal logic theory." "The thought of formal logic theory, though it cannot be said that it is not thought, is only thought of the lower order; Now that we have a higher logic of motion, we do not need formal logic theory." [2]
It is a very important philosophical discovery that Hegel saw the difference between concrete identity and abstract identity. Hegel's mistake is that he forgot that abstract identity is not a metaphysical claim, but the reasoning principle of most theories of natural science. His denial of abstract identity is against all scientific theories, and it cannot be said that all scientific theories are ridiculous. Formal logic is the distortion of the objective world and the colored glasses of human beings, but scientific research cannot do without this colored glasses, so we must accept both formal logic and dialectical logic. It is wrong to blindly negate formal logic or dialectical logic. Many useful things are not real, they are subjective. For example, concepts, probabilities, possibilities are tools, and so is formal logic. Formal logic has value, but the application of formal logic has conditions and scope, out of the scope is wrong.