Eli Hirsch

Timothy Williamson has argued that the safety condition on knowledge places certain limits on iterations of knowledge. But at the same time, Williamson claims that interpersonal iterations of knowledge aren’t so restricted as to rule out ordinary cases. The present authors show that Williamson’s discussion misconstrues the challenge to iterated interpersonal knowledge. The proper argument against interpersonal iterations is rather what the authors call a third-person argument that does not share the major weaknesses of the argument Williamson considers. The challenge that the safety condition poses to interpersonal iterations of knowledge therefore seems robust, even in ordinary cases. But the authors also identify an underlying assumption that their argument relies on, and they show that Williamson’s original argument as well as his argument against intrapersonal iterations of knowledge rely on analogous assumptions. In assessing the extent of the clash between safety and iterated knowledge, the focus must be on the viability of these assumptions.

What I call the Similarity Principle says that a word ought to denote a class of things that are more similar to each other than to other things. A closely related formulation, which I’ll here take to be equivalent, is that a word ought to denote a class of things having something in common with each other that they don’t have in common with other things. The Similarity Principle is an example of an intuitively rational constraint on the lexicon of a language. If we imagine such strange words as “gricular” or “carple”, we feel intuitively that there would be something absurd about having such words in our language, and one explanation of this—indeed the explanation that is likely first to come to a person’s mind in some rudimentary form—is that these words violate the Similarity Principle.

In Eli Hirsch’s clever and careful Dividing Reality he asks us to consider several strange languages. For example, in the Gricular language there is no word that applies to all and only green things and none that applies to all and only circular things, but there are the three words “gricular,” which applies to anything that is either green or circular, “grincular,” which applies to anything that is either green or not circular, and “ngricular,” which applies to anything that is either circular or not green. Griculese is but one of the strange languages Hirsch explores, but they are all alike in having the same descriptive content as English—anything that can be said in English can be said in the strange languages, and vice versa. For instance, to say that something is green, we can say “it is both gricular and grincular.” Our strong intuition is that these languages are strange—irrational or worse. The challenge is to ground this intuition in some particular feature of the language that makes it defective. The problem is that there seems no good response to this challenge. Hirsch examines many proposals, and rejects every one. Thus he finds himself reaching a conclusion even he finds it difficult to accept. The disturbing conclusion, division relativism by title, is that our strong intuition is misguided—the “strange” languages are just as reasonable as English.

In the work of both Matti Eklund and John Hawthorne there is an influential semantic argument for a maximally expansive ontology that is thought to undermine even modest forms of quantifier variance. The crucial premise of the argument holds that it is impossible for an ontologically "smaller" language to give a Tarskian semantics for an ontologically "bigger" language. After explaining the Eklund-Hawthorne argument (in section I), we show this crucial premise to be mistaken (in section II) by developing a Tarskian semantics for a mereological universalist language within a mereological nihilist language (a case which we, and Eklund and Hawthorne, take as representative). After developing this semantics we step back (in section III) to discuss the philosophical motivations behind the Eklund- Hawthorne argument’s demand for a semantics. We ultimately conclude that quantifier variantists can meet any demand for a semantics that might reasonably be imposed upon them.

Two main claims are defended in this paper: first, that typical disputes in the literature about the ontology of physical objects are merely verbal; second, that the proper way to resolve these disputes is by appealing to common sense or ordinary language. A verbal dispute is characterized not in terms of private idiolects, but in terms of different linguistic communities representing different positions. If we imagine a community that makes Chisholm's mereological essentialist assertions, and another community that makes Lewis's four‐dimensionalist assertions, the members of each community speak the truth in their respective languages. This follows from an application of the principle of interpretive charity to the two communities.

Two main claims are defended in this paper: first, that typical disputes in the literature about the ontology of physical objects are merely verbal; second, that the proper way to resolve these disputes is by appealing to common sense or ordinary language. A verbal dispute is characterized not in terms of private idiolects, but in terms of different linguistic communities representing different positions. If we imagine a community that makes Chisholm's mereological essentialist assertions, and another community that makes Lewis's four-dimensionalist assertions, the members of each community speak the truth in their respective languages. This follows from an application of the principle of interpretive charity to the two communities.