Under simple descriptivism, where 'Aristotle' means 'the teacher of Alexander,' consider the sentence 'Aristotle might not have taught Alexander.' What problem does this create?
AThe sentence becomes analytically true — 'the teacher of Alexander' necessarily taught Alexander, so the sentence is trivially false
BThe sentence becomes self-contradictory — you'd be saying 'the teacher of Alexander might not have taught Alexander,' which is incoherent
CThe sentence refers to a different individual in each possible world, making cross-world claims impossible
DThe sentence becomes meaningless because proper names cannot appear in counterfactual contexts
This is Kripke's modal argument against simple descriptivism. If 'Aristotle' means 'the teacher of Alexander,' then 'Aristotle might not have taught Alexander' becomes 'the teacher of Alexander might not have taught Alexander' — near-contradictory. But the original sentence seems perfectly intelligible: we can coherently imagine a world where Aristotle chose a different career. The problem is that the name rigidly designates the same individual across possible worlds, while the description picks out whoever satisfies it in each world. These can come apart, which means they can't mean the same thing.
Question 2 Multiple Choice
Suppose it is discovered that the historical person known as 'Aristotle' never actually taught Alexander. Under simple descriptivism (where 'Aristotle' = 'the teacher of Alexander'), what follows?
A'Aristotle' now refers to whoever actually did teach Alexander, or fails to refer if no one did — the name's reference tracks the description, not the person
BThe discovery is impossible — historical names are stipulatively tied to historical facts
C'Aristotle' still refers to the same individual because names are causally connected to their referents, not to descriptions
DThe name 'Aristotle' becomes meaningless until a new description is officially assigned
Under simple descriptivism, the name's reference is entirely determined by the associated description. If no one matching 'the teacher of Alexander' existed, the name either refers to whoever does satisfy the description (potentially a different person) or fails to refer at all. This is one of the problems Kripke identifies: intuitively, 'Aristotle' should still refer to that specific Greek philosopher even if we turn out to be wrong about what he did. Direct reference theory handles this naturally; simple descriptivism cannot.
Question 3 True / False
On Kripke's view, 'Aristotle' refers to the same individual in every possible world where that individual exists, even in worlds where Aristotle never taught philosophy or wrote a single work.
TTrue
FFalse
Answer: True
This is the definition of a rigid designator: a name picks out the same individual across all possible worlds in which that individual exists, regardless of which descriptions that individual happens to satisfy in those worlds. In a world where Aristotle became a merchant instead, 'Aristotle' still refers to him. The description 'the teacher of Alexander' would fail to pick him out in that world — but the name wouldn't. This rigidity is what distinguishes names from descriptions.
Question 4 True / False
Descriptivism and direct reference theory agree that proper names have both a sense (descriptive content) and a reference (the object named).
TTrue
FFalse
Answer: False
This is precisely the disagreement between them. Descriptivism holds that names have sense — they abbreviate descriptions and thus have cognitive/semantic content beyond mere reference. Direct reference theory (Kripke, Mill) holds that names have only reference: they directly tag individuals in the world, with no descriptive sense. The Millian slogan is that a name is just a 'tag' or 'label.' This dispute about whether names have sense is one of the central issues in the descriptivism vs. direct reference debate.
Question 5 Short Answer
What is the key test Kripke uses to show that proper names cannot mean the same as descriptions, and how do names and descriptions behave differently under this test?
Think about your answer, then reveal below.
Model answer: Kripke's key test is modal — what the term refers to across possible worlds. A name rigidly designates the same individual in every possible world where that individual exists: 'Aristotle' refers to that specific person even in worlds where he chose a different career. A description is not rigid: 'the teacher of Alexander' picks out whoever satisfied that description in each world, which might be a different person in a world where Aristotle became a merchant. Because names and descriptions can come apart across possible worlds, they cannot mean the same thing.
The rigidity test is powerful because it reveals a structural difference, not just a practical one. It's not merely that we happen to associate different descriptions with names — it's that names and descriptions have fundamentally different semantic mechanisms. Names pick out individuals essentially; descriptions pick out whoever fits, and the fit can vary by world.