Descartes argues that geometric truths about triangles are known with certainty through pure reason, independent of any experience. How would Hume respond to this claim?
AHume would agree — geometry is a matter of fact that pure reason can establish through careful proof
BHume would say geometric truths are 'relations of ideas' — necessarily true and knowable a priori, but analytic: they reveal nothing about the actual physical world, only the relations among our concepts
CHume would deny that geometric truths are knowable at all, since the senses are unreliable
DHume would agree that geometry is innate knowledge, just not implanted by God
Hume's fork divides all meaningful claims into relations of ideas (analytic, necessary, a priori — true by definition or logical structure) and matters of fact (synthetic, contingent, a posteriori — verified by experience). Geometric truths fall into the first category: they are certain and a priori, but only because they unpack the relations among our own concepts. They tell us nothing about the external world — whether actual physical space is Euclidean is a matter of fact. This lets Hume concede mathematical certainty while denying that reason gives us substantive knowledge of reality, which is his core empiricist move.
Question 2 Multiple Choice
A philosopher claims: 'The causal principle — that every event must have a cause — is a necessary truth known through reason alone, not merely a generalization from experience.' Which philosophical position does this most closely represent?
AHume's empiricism, because he argued causal knowledge comes from rational inference about observed regularities
BLocke's empiricism, because he believed the mind begins as a blank slate open to experience
CRationalism, because the claim asserts that pure reason yields substantive knowledge of how reality must be structured
DKant's empiricism, because he held that experience provides all content of knowledge
Claiming that causal necessity is knowable a priori through reason — not merely observed as a pattern — is the paradigmatic rationalist move. Rationalists (Descartes, Leibniz, Spinoza) hold that reason can yield substantive knowledge of reality's structure. Hume's response is the decisive empiricist rebuttal: we observe constant conjunction (A is always followed by B) but never necessary connection. Causal necessity is a habit of inference, not a feature of the world that reason can establish. Kant's synthesis is that causality is real but as a form the mind imposes on experience, not a free-standing feature of the mind-independent world.
Question 3 True / False
Kant holds that knowledge of the external world is possible through sensory experience alone, and that the mind passively receives and records experience without contributing any structure of its own.
TTrue
FFalse
Answer: False
This describes Locke's empiricist picture of the mind as a blank slate — not Kant's view. Kant's central innovation is that the mind actively structures experience: space, time, and causality are not features we discover empirically but forms the mind imposes on raw sensory input, making coherent experience possible at all. Without the mind's contribution, there would be no organized perception. This is Kant's 'Copernican Revolution' in philosophy — the turn from asking what the mind must discover to asking what the mind must contribute.
Question 4 True / False
Hume's 'fork' implies that metaphysical claims about causation as a necessary connection or about God's existence are, strictly speaking, meaningless — neither true nor false, but simply outside the bounds of genuine cognition.
TTrue
FFalse
Answer: True
Hume's fork leaves no room for traditional metaphysics. If a claim is not a relation of ideas (analytic, a priori) and not a matter of fact (empirically verifiable), it has no legitimate cognitive content. Claims about God's existence, the necessary connection between cause and effect, or the persistence of the self through time don't fit either category — they cannot be verified by experience and are not merely definitional. Hume's famous conclusion: 'Commit it then to the flames: for it can contain nothing but sophistry and illusion.' This is as radical an empiricist move as can be made.
Question 5 Short Answer
Why is Kant considered a synthesis of rationalism and empiricism rather than a member of either camp? What does each tradition contribute to his view?
Think about your answer, then reveal below.
Model answer: Kant takes from empiricism the insistence that experience is necessary for knowledge — we cannot know the world through pure reason alone, and all genuine knowledge must connect to possible experience (ruling out speculative metaphysics). He takes from rationalism the insight that the mind contributes structure that cannot itself be derived from experience — space, time, and causality are a priori forms that make experience possible. Experience provides the content (sensory data); the mind provides the form (the categories that organize data into intelligible experience). Neither tradition alone is sufficient: pure empiricism cannot account for the necessity and universality of mathematics and causality; pure rationalism cannot account for why reason must connect to experience to yield genuine knowledge.
Kant's synthetic a priori is the key move: judgments like '7+5=12' are both necessarily true (a priori) and genuinely informative about possible experience (synthetic, not merely analytic). These are possible because the mind's mathematical forms are imposed on all experience — the world, as we can know it, is necessarily mathematical. The cost is Kant's agnosticism about things-in-themselves (noumena): we know only phenomena (the world as structured by our minds), never the world as it is independent of our cognitive contribution.