Remarks

Short, focused remarks on philosophical questions adjacent to the formal material — the kind of conceptual fine print that motivates or interprets the technical pages.

Contents

1. Semantics and the Theory of Meaning — what it is for an expression to mean something: reference and truth-conditions, use and inferential role, the major theories (Frege, model-theoretic, verificationist, truth-conditional, use theories), and how mathematical/model-theoretic semantics relates to meaning in natural language.
2. Space and Time in Special Relativity — what time and space are and how each is measured once relativity replaces Newton's absolute time and space: time as the operational reading of a clock and proper length of a worldline, space as a frame-relative slice with proper length as its invariant, length contraction and the collapse of the universal "now" as two faces of relative simultaneity, and the causal structure that survives — the physical entry point to the Philosophy of Space and Time.
3. The Philosophy of Bell's Theorem — an experimental metaphysics in two movements: first a fully explicit derivation of the CHSH inequality, its quantum violation, and Tsirelson's bound; then the philosophical reckoning — what exactly is refuted ("local realism" vs. locality simpliciter), the Jarrett–Shimony split of locality into parameter- and outcome-independence ("passion, not action, at a distance"), the assumptions of measurement independence and free choice (superdeterminism, retrocausality), the experimental loopholes and their loophole-free closure, and the menu of interpretations sorted by which premise each sacrifices.
4. Necessity and Metaphysics — the modal notions modern metaphysics runs on: Kripke's Naming and Necessity (the case against descriptivism, rigid designation, the causal–historical picture, and the prising apart of the necessary, the a priori, and the analytic), and metaphysical necessity itself — its place between logical and nomological modality, its standard sources, the competing analyses (possible worlds, ersatzism, essence, and the eliminativist, reductive, and expressivist grades of deflationism), where Kripke himself stands among them, and the standing problem of how modal knowledge is possible; then two case studies in what the workhorse examples actually show — "water is H₂O" is ambiguous between molecular, compositional, kind-identity, and constitution readings whose modal statuses differ, and "gold is the element with atomic number 79" states a criterion chemistry itself adopted, so in both cases the necessity rests on an essentialist premise the science does not supply — then the question of how far the de re defence against these deflations must itself presuppose a theory of reference, and why neither party occupies language-neutral ground, closing with Hesperus is Phosphorus and three grades of framework-dependence that separate what a scientific framework contributes to a modal claim from what it does not, and with the historical form of the deflation — whether the discovery of a necessity is just a criterion being installed and entrenched, why the genetic and explanatory-redundancy versions of that argument differ in strength, and what the record of revised "necessities" does and does not show; and finally whether realist and deflationist idioms are intertranslatable at all — the counterpart-theory precedent, two-dimensional semantics as the candidate manual, and the three joints (absoluteness, modal error, explanatory priority) where the mapping leaks — ending with a balance sheet of the two positions' explanatory debts, which pair off almost exactly: objectivity and error against epistemology and criterion.