Where do certain kinds knowledge come from?
When we talk about a priori cognition, we are dealing with knowledge that does not come from observation or experience. Because it does not come from experience, Kant argues that it cannot be taken from the objects themselves. If you never observed something, you cannot claim the object told you anything about itself.
So where does the content come from? Kant’s answers that it comes from the structure of the mind itself. When we claim something a priori about objects, we are not discovering a property that the object independently revealed. We are describing the framework that the mind already uses to organize whatever it encounters.
When reason makes a priori judgments about objects, it is actually describing the rules that the mind itself contributes, not the intrinsic nature of the objects. To see the point, take the idea of causality. If a glass falls and breaks, the mind immediately interprets the sequence as: impact → causes → breaking
But Kant argues that experience alone cannot logically prove that events must follow causal laws. We only ever observe sequences of events. The necessity that “one event must produce another” is not something we directly see. Kant therefore claims that causality is not extracted from objects. It is one of the categories of the understanding a built-in rule that the mind uses to interpret events.
So when we say “events have causes,” we are partly describing how the mind organizes experience, not reporting a property that we independently inspected in reality. The same applies to space and time. According to Kant, these are not features we learned from objects; they are the mental forms through which objects appear to us at all.