In this paper it will be argued that any realist interpretation of quantum mechanics intending to preserve the objectivity of the set of the definite-valued observables should require such a set to be invariant under the symmetry group of the theory. In particular, it will be shown that the natural way to reach this goal is to appeal to the Casimir operators of the Galilean group. Additionally, this idea will be generalized in two ways: by selecting the definite-valued observables of (...) a system in quantum field theory as those represented by the Casimir operators of the Poincaré group, and by extending the strategy to gauge symmetries. (shrink)

Philosophers and psychologists often distinguish episodic or personal memory from propositional or semantic memory. A vexed issue concerns the role, if any, of memory “impressions” or “seemings” within the latter. According to an important family of approaches, seemings play a fundamental epistemological role vis-à-vis propositional memory judgments: it is one’s memory seeming that Caesar was murdered, say, that justifies one’s judgment that he was murdered. Yet, it has been convincingly argued that these approaches lead to insurmountable problems and that memory (...) seemings are not wellsuited to play this justifying role. As a result, many contemporary accounts of propositional memory dispense with these seemings altogether. Is the idea that memory seemings play a key role in propositional memory really the result of bad theorizing? My aim is to shed light on this issue, which I will approach as follows. In Section 1, I contrast episodic memory with propositional memory so as to clarify the nature of the latter. According to the account I put forward, episodic memory consists in the preservation of acquaintance with objects and events, whereas propositional memory consists in the preservation of thought contents. In Section 2, I turn my attention to the contrast between propositional memory contents and propositional memory as an attitude. I argue that they play different roles. Memory contents satisfy a past awareness constraint and a causal constraint; the attitude of remembering explains why we are inclined to endorse these contents. This distinction leads me to explore the attitude of remembering, and I argue, in Section 3, that the most appealing account of this attitude is in terms of feelings of familiarity. In Section 4, I turn my attention to the epistemology of propositional memory and revisit the claim that propositional memory judgments are justifi ed by memory seemings. In so doing, I contend that the attitude of remembering plays an exclusively explanatory role and does not contribute to the epistemology of propositional memory judgments. I conclude by drawing a more general lesson regarding the respective roles of attitudes and contents. (shrink)

In the philosophical tradition, the notions of determinism and causality are strongly linked: it is assumed that in a world of deterministic laws, causality may be said to reign supreme; and in any world where the causality is strong enough, determinism must hold. I will show that these alleged linkages are based on mistakes, and in fact get things almost completely wrong. In a deterministic world that is anything like ours, there is no room for genuine causation. Though there may (...) be stable enough macro-level regularities to serve the purposes of human agents, the sense of “causality” that can be maintained is one that will at best satisfy Humeans and pragmatists, not causal fundamentalists. (shrink)

A quantum state represents neither properties of a physical system nor anyone's knowledge of its properties. The important question is not what quantum states represent but how they are used as informational bridges. Knowing about some physical situations, an agent may assign a quantum state to form expectations about other possible physical situations. Quantum states are objective: only expectations based on correct state assignments are generally reliable. If a quantum state represents anything, it is the objective probabilistic relations between its (...) backing conditions and its advice conditions. This paper offers an account of quantum states and their function as informational bridges, in quantum teleportation and elsewhere. (shrink)