- Empirical grounds(as a reason for rejection)
- Based on real observations and experiments rather than pure theory or logic—if something is rejected on empirical grounds, experiments showed it doesn't match reality.
- Hume(as the main philosopher discussed in this statement)
- David Hume was an 18th-century Scottish philosopher who argued that human knowledge comes from experience and observation rather than pure reasoning alone.
- Intrinsic feature(as used in metaphysics (the study of what exists))
- A characteristic that belongs to something naturally, as part of its basic nature, rather than depending on outside factors.
- P2(Provides the truth conditions for proposition (7), identified as proposition (7): George Bush does not exist.)
- The principle that proposition (7) is true if and only if George Bush does not exist — a modalized instance of the Tarski truth-schema 's is true iff s'.
- Regularity theory(the main theory being described)
- The idea that causation isn't some mysterious force or power, but simply a reliable pattern where one type of event consistently follows another type of event.
- causal necessity(Hume's account in EHU 7.2.28–29; 8.1.5)
- The constant conjunction of similar objects together with a customary inference of the mind from one to the other; the feeling of necessary connection is a product of the imagination, not an objective force in the world.
- constant conjunction(Central concept in Hume's account of causation)
- A relation between two types of events such that one has always been followed by the other throughout observed experience.
- necessitation(Used to move from K(p ∧ ¬Kp) is false to K(p ∧ ¬Kp) is necessarily false in Fitch's argument)
- An inference rule by which, if a statement is (provably) false, it is necessarily false