Kant’s Theory of Knowledge: Exploring the Limits of Understanding
Synthetic Judgments a Priori
Summarizing the previous section, Kant’s primary question is: What can we truly know? His answer, broadly speaking, is that we can genuinely know anything that can be subjected to scientific inquiry.
This leads to the question: What types of judgments are considered scientific? Before addressing this, Kant classifies different types of judgments and identifies those that meet the necessary criteria for scientific knowledge.
Analytic and Synthetic Judgments
Kant distinguishes between analytic and synthetic judgments.
An analytic judgment, according to Kant, occurs when the predicate is contained within the subject. For example, “The whole is greater than its parts” is an analytic judgment. We understand the meaning of “whole” and recognize that the predicate doesn’t add any new information not already present in the subject. These judgments don’t provide new information or, as Kant puts it, are not extensive; they don’t expand our knowledge.
Conversely, a synthetic judgment occurs when the predicate adds information not included in the subject. For example, “All natives of village X are taller than 1.90 meters” is a synthetic judgment. These judgments do provide new information or, as Kant says, are extensive, expanding our knowledge.
A Priori and A Posteriori Judgments
This classification is based on how we can know the truth of a judgment.
A priori judgments are those whose truth can be known independently of experience. For example, “The whole is greater than its parts” is an a priori judgment. We know its truth without needing to measure or observe all parts. A priori judgments are universal and necessary.
A posteriori judgments are those whose truth is known through experience. For example, “All natives of village X are taller than 1.90 meters” is an a posteriori judgment. To determine its truth, we must observe the individuals in question. A posteriori judgments are not universal or necessary.
Synthetic A Priori Judgments
Consider the statement: “The straight line is the shortest distance between two points.” Is this an analytic judgment? Kant argues no, because the predicate is not contained in the subject. The concept of a straight line doesn’t inherently include the idea of distance. Therefore, it’s synthetic. Is it a posteriori? Again, Kant argues no, because we know its truth without measuring distances between two points. Furthermore, it’s universally and necessarily true. Therefore, it’s a priori.
According to Kant, synthetic a priori judgments exist. Being synthetic, they are extensive, expanding our knowledge. Being a priori, they are universal and necessary; knowledge of their truth doesn’t depend on experience.
Synthetic a priori judgments are the foundation of scientific knowledge. They alone allow us to have true knowledge of reality.
The Limits of Knowledge
Based on the previous discussion, we can conclude that our knowledge is limited to what can be expressed through synthetic a priori judgments. However, the question of the limits of knowledge in Kant relates more specifically to how our understanding develops knowledge.
This process is detailed in the Critique of Pure Reason and unfolds in three stages, corresponding to the work’s three parts: the Transcendental Aesthetic, the Transcendental Analytic, and the Transcendental Dialectic.
The Transcendental Aesthetic
In this first part, Kant explains that reason has two fundamental mechanisms or coordinates: space and time.
To achieve the most basic level of knowledge, these two a priori forms of sensibility must act upon the unorganized sensations that form the basis of our perception of the world. Thanks to the a priori forms of space and time, our reason orders and organizes the data from the external world.
Transcendental Analytic
In this second part, Kant examines the conditions under which we can think or understand the data organized through the coordinates of space and time.
These coordinates are essentially other structures of reason: pure concepts or categories. In addition to these, our reason also possesses empirical concepts derived from experience, such as the concepts of house, dog, mammal, etc.
What is the role of pure categories? Simply put, they organize the sensations produced by the things around us once they have been structured spatiotemporally.
For example, when encountering the natives of village X, our reason first perceives a set of spatial data occurring over time. Then, our understanding applies empirical concepts like shapes and colors to this data. Finally, our intellect coordinates and unifies these sensations by applying certain categories, such as reality, substance, and whole.
Kant concludes this section by highlighting the difference between the phenomenon and the thing-in-itself.
The phenomenon is the appearance of the object as perceived by our understanding after it has applied spatiotemporal coordinates, empirical concepts, and categories.
The thing-in-itself is the object’s complete reality, independent of our perception. The thing-in-itself always has aspects that remain hidden from us. We only know the phenomena of things, not the things-in-themselves.
Transcendental Dialectic
In this final part, Kant explains that reason drives us to seek increasingly general laws and principles that can explain a wider range of phenomena. When this search remains within the limits of experience, it’s effective and expands our knowledge.
However, reason sometimes goes beyond the limits of experience, attempting to unify and explain physical phenomena through metaphysical theories about the world, the soul, and the cause of all that exists.
World, Soul, Self, and God are ideas of reason that don’t provide objective knowledge but express reason’s ideal of finding increasingly general principles and laws.