How would I know?
That which aligns with Kantian and phenomenological views is that an object of consciousness is constituted by its attributes (predicates, properties) -through which it is known. Without attributes, it remains indeterminate and unknowable. We cannot assert that a thing exists without predicates, because existence is not a predicate that adds to the concept of a thing. To meaningfully speak of existence, we must already have a determinate concept—formed by predicates—of what it is that might exist. Without predicates, there is no object of thought, and thus no basis for asserting existence.
A concept cannot exist without predicates.
For Kant, a concept is defined as a function that unifies representations under a common feature—its predicates. A concept without predicates would have no content, no defining characteristics, and thus could not represent any object or serve in judgment. As Kant states, concepts are "predicates of possible judgments"; without predicates, there is no basis for thought or reference.
Restated, a concept without any predicates is not possible. For Kant, a concept is defined by its predicates—its defining characteristics or properties. A "concept" stripped of all predicates would be empty, indeterminate, and incapable of referring to any object, real or imagined. Even the most abstract concepts (e.g., "thing in itself") rely on minimal conceptual determination. Without predicates, there is no basis for thought or judgment.
Existence without predicates is not possible in any meaningful sense. For Kant, to speak of an object—even as existing—requires conceptual determination. Existence is not a predicate that adds to the concept of a thing, but we cannot meaningfully assert that something exists unless we already have a concept of what it is (i.e., its predicates). A completely bare existence, devoid of all properties, is not an object of possible experience or thought.
Kant’s central objection to the ontological argument is that existence is not a predicate. He argued that saying something exists does not add a property (like being red or round) to its concept. For example, a hundred real thalers contain no more money than a hundred possible thalers—the concept is unchanged. Existence is not part of a thing’s essence; it signifies that a concept is instantiated in reality.
Space, to give a practical example, is not void or nothing. For Kant, space is a necessary form of intuition—structured, unified, and presupposing synthesis. Dimensions are not added conditions but intrinsic to space as we experience it. Without synthetic unity (of apperception and sensibility), no object, including spatial magnitude, can be given. The space within a one-inch square does not equal the space in a two-inch square, even if both are void.
For Kant, space is not nothingness or void—it is a pure "a priori" intuition that provides the structure for all spatial magnitude. Size and extension are intrinsic to space as we experience it. A two-inch square has greater spatial magnitude than a one-inch square because spatial relations (like size) are given through intuition, not derived from empirical measurement.
To claim that nothing is nothing misunderstands space as mere absence (void), whereas for Kant, space is the necessary form of outer sense—structured, measurable, and inherently differentiated by dimension. The statement "a thing is what it is" is a tautology—it is true by logical form (e.g., A = A), but provides no new information. Its complement, "everything else is what it is not," is not a tautology. It expresses a contrast or negation, not a logical necessity. It can be false in certain contexts and does not hold universally like a tautology.
A tautology is not a faulty synthetic statement. A tautology is an analytic statement (e.g., "All bachelors are bachelors")—true by definition. A synthetic statement adds new information and cannot be tautological by nature. Faulty synthetic statements would be those falsely claimed to be necessarily and universally true without experience, but they fail due to incorrect content (e.g., "The sum of two sides of a triangle is less than the third" — false, yet synthetic). Tautologies belong to analytic judgments; they are not synthetic at all.
There are no true examples of a synthetic statement that is necessarily and universally true without relying on experience but is also false—because if it's necessarily and universally true, it cannot be false. However, a common error is mistaking an analytic truth for a synthetic one. For example, someone might falsely claim:
> "A straight line is straight"
-as a synthetic necessary truth. But this is actually analytic—the predicate "straight" is already contained in the subject "straight line." The error is treating a tautological, definitional truth as if it expands knowledge like a genuine synthetic "a priori" judgment (e.g., "a straight line is the shortest distance between two points"). Kant’s intention was identifying the source of necessity and universality.
The following statements:
"The sum of the interior angles of a triangle is equal to 180 degrees."
"Two straight lines cannot enclose a space."
"For any triangle, the length of one side is less than the sum of the lengths of the other two sides (triangle inequality)."
-are synthetic, necessary, and universally true without being derived from experience.
"The shortest distance between two points is a straight line" is a synthetic statement that is necessarily and universally true without relying on experience.
"7 + 5 = 12" is a synthetic statement that is necessarily and universally true without relying on experience.
A synthetic "a priori" proposition is a statement that adds new knowledge not contained in the subject concept (synthetic), yet is known to be necessarily and universally true independent of sensory experience. Synthetic "a priori" refers to a type of proposition or judgment, not a standalone concept or object. It describes statements that are:
1. Synthetic: The predicate is not contained in the subject (e.g., "7 + 5 = 12" adds new knowledge).
2. A priori: Known independently of experience, with necessity and universality.
Mathematical truths ("5 + 7 = 12"), geometrical judgments ("a straight line has extension"), and principles of natural science ("every event has a cause"), are propositions which depend on pure intuitions (e.g., space and time), and categories of understanding, for their justification.