In a field often bogged down by dense abstraction, Jeffrey Kaplan delivers a rare clarity on the 1970 lectures that shattered a decades-old consensus in philosophy. The piece doesn't just recount history; it isolates the precise logical fracture where the dominant theory of language collapsed under the weight of a single, elegant counter-argument. For the busy mind seeking to understand how we actually refer to the world, this is the essential pivot point.
The Death of the Cluster
Kaplan sets the stage by introducing the intellectual landscape of 1958, when John Surl's "cluster theory" held sway. The prevailing wisdom was that a name like "Abraham Lincoln" was merely a shorthand for a bundle of descriptions: the 16th president, the issuer of the Emancipation Proclamation, the man from the log cabin. Kaplan notes that under this view, "proper names like Abraham Lincoln are really just synonymous they really have the same meaning as descriptions like the 16th president of the United States." This framing is crucial because it reduces the act of naming to a simple act of definition, a move Kaplan suggests is intuitively appealing but logically fragile.
The author then dissects Surl's six theses, focusing on the idea that these descriptions must uniquely identify a single individual. Kaplan paraphrases the core claim: "the unique object with the weighted majority of the properties is the referent." This is the heart of the cluster theory—the notion that if enough descriptions fit, the name latches onto that person. However, Kaplan immediately flags the vagueness here, noting that "some of these properties might be more important than others and so they get more weight or something like that."
"The point is just whichever thing fits with enough of these that is the reference of the name that guy whoever meets enough of these characteristics that's Abraham Lincoln."
This reliance on a "weighted majority" is the theory's first vulnerability. It introduces an amorphous standard into a field demanding precision. If the criteria for reference are fuzzy, the theory cannot reliably explain how communication works. Critics might argue that human language is inherently fuzzy, but Kaplan's analysis suggests that a theory of reference needs to account for certainty, not just probability.
The Contingency Trap
The commentary then shifts to the most devastating blow Kaplan identifies: the confusion between what is true and what must be true. Kaplan explains the distinction between contingent truths (things that happened to occur) and necessary truths (things that could not have been otherwise). He illustrates this with the election of 1860: "Abraham Lincoln won the election of 1860 that sentence is true but it just happened by chance to be true."
If the cluster theory were correct, the name "Abraham Lincoln" would be synonymous with "the winner of the 1860 election." Consequently, the statement "Abraham Lincoln won the election of 1860" would be a necessary truth, true in all possible worlds. Kaplan dismantles this by pointing out the absurdity: "it's not necessarily true that Abraham Lincoln was the 16th president of the United States... maybe he just stayed in Kentucky where he was born... never became a politician or anything like that."
This is where Kaplan introduces the concept of the "rigid designator," though he wisely refers the reader to a separate explanation for the technical mechanics. The core insight remains accessible: a name points to the same individual regardless of what that individual does. As Kaplan puts it, "a proper name like Abraham Lincoln is a rigid designator because it continues to designate it continues to refer to the same guy Abraham Lincoln even in those other possible worlds." This distinction is the piece's intellectual anchor, separating the person from the properties we associate with them.
The Failure of Uniqueness
Kaplan moves next to attack the idea that the average person possesses a unique set of descriptions for famous figures. He uses the example of Cicero, noting that most people know him simply as "a famous Roman orator." This description is hardly unique. Kaplan writes, "most people when they think of Cicero just think of a famous Roman orator without any pretension to think either that there is only one famous Roman orator or that one must know something else about Cicero to have a reference for the name."
He extends this to modern figures like Richard Feynman, mocking the expectation that a layperson could distinguish him from a peer like "Gilman" through specific theoretical knowledge. "The man in the street not possessing these abilities may still use the name finan when asked he will say well he's a physicist or something." The argument here is that successful reference does not require unique identification. We can talk about Feynman meaningfully even if our mental cluster of descriptions is too broad to pick him out from a crowd of physicists.
"The point is just that thesis 2 is false the descriptions that people have in their heads that they associate with proper names proper names that they can use in the normal way meaningfully to refer to people those descriptions that cluster of properties it's not enough to uniquely pick out some object in the world."
This is a profound observation about the mechanics of social knowledge. It suggests that reference is a social act, not a private mental calculation. The cluster theory fails because it demands a level of individual cognitive precision that simply does not exist in daily life.
The Gödel Thought Experiment
Finally, Kaplan details the most famous part of Kripke's lecture: the fictional scenario involving Kurt Gödel. Kaplan sets up the thought experiment with a touch of humor, noting Kripke's remark, "I hope that Professor girdle is not present," before launching into a story where Gödel never discovered the incompleteness of arithmetic, and a man named Schmidt did.
In this scenario, the descriptions associated with the name "Gödel" (the man who proved the incompleteness theorem) would actually apply to Schmidt. Yet, Kaplan argues, we would still say "Gödel did not prove the theorem," not "Schmidt did." The name "Gödel" would still refer to the man we call Gödel, even if he failed to produce the work we attribute to him. This thought experiment serves as the final nail in the coffin for the idea that descriptions determine reference. The name sticks to the person, not the achievements.
Bottom Line
Jeffrey Kaplan's commentary succeeds by stripping away the technical jargon of analytic philosophy to reveal a fundamental truth about how language functions: names are anchors, not descriptions. The strongest part of the argument is the demonstration that our ability to refer to people does not depend on our knowledge of their specific attributes. The piece's only vulnerability is its heavy reliance on the reader's prior familiarity with the concept of "possible worlds," which Kaplan admits is a prerequisite for full comprehension. For the time-pressed reader, the takeaway is clear: we refer to people directly, not through a filter of what we think they did.