Why did Kant say that the object must conform to our understanding? The main reason is that we have to use abstract method of understanding. This abstract method is a pair of colored glasses that we have to wear.

What is a chicken plus a dog? Is it equal to two chickens or two dogs? Obviously neither. But we can say that one plus one equals two, because we have made abstraction first before we do this calculation. What does it mean when we say “one”? It is an abstraction of a chicken, a dog, a person, an earth, everything. Scientific research cannot do without formal logic, and the premise of formal logic is abstraction. So scientific research can never do without abstraction. The abstract process can only take place in the subjective world. In the objective world there are only concrete things, there are no abstract things. In the concrete objective world, no two leaves are the same, and one is never equal to one. In the abstract subjective world, one can be equal to one. So scientific research can never jump out of the subjective world.

Materialism, subjective idealism and objective idealism are all wrong theories. Materialists only saw the subjective world as part of the objective world, but they did not see that objective world is a part of the subjective world. Although subjective idealism sees that the objective world is a part of the subjective world, it denies the existence of the objective world. Objective idealism regards the content of the subjective world as the content of the objective world.