這件事說明，康德三百年前，就企圖從形下重建形上，這明顯就是車行形上學，
Immanuel Kant’s “Physical Monadology” (1756) and Gottfried Wilhelm Leibniz’s “Monadology” (1714) are both significant works exploring the fundamental nature of reality, but they diverge in their underlying metaphysical frameworks and methodologies. While Leibniz’s Monadology is a purely metaphysical and idealist system, Kant’s Physical Monadology attempts to reconcile metaphysical speculation with the emerging scientific understanding of the natural world, particularly Newtonian physics.
Kant’s Physical Monadology (1756)
Overview:
• In his Physical Monadology, Kant investigates the fundamental building blocks of physical reality. He proposes a theory of physical monads, combining metaphysical insights with the scientific principles of matter and motion.
• Kant’s goal is to provide a unified account of the continuity of matter, reconciling the idea of indivisible units (monads) with the divisibility observed in physical phenomena.
Key Ideas:
1. Monads as Physical Points:
• Unlike Leibniz’s purely metaphysical monads, Kant’s monads are physical entities, extended and located in space, though indivisible.
• They are not spiritual or immaterial; instead, they are physical points of force that constitute matter.
2. Forces as Fundamental:
• Kant argues that matter is not made of inert particles but of forces. Specifically:
• Attractive force (gravity): Holds matter together.
• Repulsive force: Prevents matter from collapsing into a single point.
• These forces form the basis of his monadological view of matter.
3. Continuity of Matter:
• Kant seeks to reconcile the apparent divisibility of matter with the idea of indivisible units. He suggests that matter appears divisible because it is composed of monads interacting through forces.
4. Dynamic Conception of Matter:
• Kant’s physical monads are dynamic units, emphasizing motion and interaction over static substance. This reflects the influence of Newtonian mechanics on Kant’s thought.
Leibniz’s Monadology (1714)
Overview:
• Leibniz’s Monadology is a purely metaphysical system that posits monads—simple, immaterial, indivisible, and self-contained units—as the ultimate constituents of reality.
• Monads are metaphysical points of pure substance, without extension in space, and they possess perception and appetition (the tendency to change).
Key Ideas:
1. Monads as Simple Substances:
• Monads are indivisible and lack spatial extension, making them metaphysical rather than physical entities.
• They are independent centers of reality, preprogrammed by God to harmonize with one another in a pre-established harmony.
2. Perception and Consciousness:
• Each monad reflects the entire universe from its unique perspective. They have varying degrees of perception, with higher monads (like human souls) having clearer perceptions and consciousness.
3. No Interaction Between Monads:
• Monads do not interact causally with each other. Their changes are internally determined and synchronized by God’s pre-established harmony.
4. Idealism:
• Leibniz’s monads are purely spiritual entities, emphasizing the primacy of mind and ideas over material reality.
Comparison: Kant’s Physical Monadology vs. Leibniz’s Monadology
Aspect Kant’s Physical Monadology (1756) Leibniz’s Monadology (1714)
Nature of Monads Physical entities, indivisible points of force. Metaphysical, immaterial, simple substances.
Primary Focus Explaining the physical structure of matter. Explaining the metaphysical structure of reality.
Interaction Between Monads Monads interact through forces (attraction and repulsion). No interaction; changes are pre-established by God.
Role of God Not central to the system, though implicitly assumed. Central to the system; God ensures harmony.
Extension in Space Monads are located in space and contribute to physical phenomena. Monads are non-spatial and purely immaterial.
Scientific Basis Grounded in Newtonian mechanics and natural philosophy. Purely metaphysical and idealist framework.
Emphasis Dynamic, physical forces driving motion and matter. Perception, consciousness, and metaphysical unity.
Key Differences:
1. Metaphysical vs. Physical:
• Leibniz’s monads are purely metaphysical, forming the foundation of an idealist system.
• Kant’s monads are physical entities, reconciling metaphysics with empirical science.
2. Role of Forces:
• Kant emphasizes dynamic forces (attraction and repulsion) as the essence of physical reality.
• Leibniz focuses on perception and pre-established harmony, with no forces or physical interactions.
3. Causality and Interaction:
• Kant’s monads interact causally through physical forces.
• Leibniz’s monads operate independently, their changes pre-coordinated by God.
4. Epistemological Goals:
• Kant is concerned with explaining how matter works in physical space.
• Leibniz seeks to explain the ultimate metaphysical nature of reality.
Significance of Kant’s Physical Monadology
1. Transition to Critical Philosophy:
• Physical Monadology represents Kant’s pre-critical phase, where he attempts to combine metaphysics with Newtonian physics. This work reflects his early engagement with scientific and metaphysical questions that would later culminate in his critical philosophy.
2. Dynamic Conception of Matter:
• Kant’s view of matter as composed of forces influenced subsequent thinkers, including those in German Idealism and modern physics.
3. Rejection of Pure Idealism:
• Unlike Leibniz, Kant emphasizes the physical and spatial aspects of reality, paving the way for his later focus on the conditions of experience in his critical philosophy.
Conclusion
Kant’s Physical Monadology can be seen as an attempt to bridge Leibnizian metaphysics with Newtonian physics, proposing a view of reality grounded in physical forces rather than purely immaterial substances. While Leibniz’s Monadology remains a masterpiece of idealist metaphysics, Kant’s work reflects his growing interest in grounding metaphysics in the empirical world, a theme that would later define his critical philosophy. The difference between the two lies in their approach: Leibniz’s monads are spiritual and metaphysical, while Kant’s monads are physical and dynamic, representing an early attempt to integrate metaphysics with science.
