This chapter is devoted to the Bohr complementarity principle.This is one of the basic quantum principles. We dissolve it into separate subprincipleson contextuality, incompatibility, complementary-completeness,and individuality. We emphasize the role of the contexuatlity component. It is not highlighted in the foundational discussions. ByBohr, the outputs of measurements are resulted from the complexinteraction between a system and measurement context, the values ofquantum observables cannot be treated as objective properties of systems.Such Bohr contextuality is more general than joint measurement contextuality(JMC) considered in the discussions on the Bellinequality. JMC is a very special form of the Bohr contextuality. The incompatibility component is always emphasized and often referred as the wave-particle duality. The principle ofinformation complementary-completeness represents Bohr’s claim on completenessof quantum theory. The individuality principle is basic for thenotion of phenomenon used by Bohr to emphasize the individuality and discreteness of outputs of measurements. Individuality plays the crucial role in distinguishing quantum and classical optics entanglements.

This is the first ever English translation of Heisenberg’s unpublished response to the EPR paper. In this chapter, Heisenberg uses his famous cut argument to argue against the possibility of hidden variables.

Schrödinger’s reaction to the EPR paper is less widely known than, say, Bohr’s, and yet our analysis shows that it fits rather nicely with contemporary concerns in foundations of quantum mechanics. Taking the lead both from the EPR paper and from Pauli’s remarks in their correspondence, Schrödinger shows that EPR’s locality considerations lead to the assignment of values to all quantum mechanical observables, but that under apparently mild assumptions this then leads to contradictions of the von Neumann type. This dilemma (as he explicitly calls it) is thus similar to more recent debates between nonlocality on the one hand and no-go results on the other (whether through violation of the Bell inequalities, the Kochen–Specker theorem, or what you will). We shall first look at Schrödinger’s fundamental worries in the years leading up to 1935. The chapter then discusses in detail the direct reaction by Schrödinger to EPR. It will, however, not exhaust our discussion of Schrödinger, who is a recurring character in the book, having poked and prodded his peers on EPR during the whole summer and autumn of 1935.

This chapter introduces in more comprehensive fashion than elsewhere in the literature the interesting role of Heisenberg in the EPR debate. Although we have already published an analysis of Heisenberg’s posthumously published draft response to EPR, only now are we able to situate this excellent primary source in its fullest context, by contributing a chapter describing, for example, Heisenberg’s thinking prior to EPR about interacting systems and hidden variables, the crucial role of Grete Hermann for Heisenberg’s thinking about separability, completeness and observational context, and describing the correspondence between Heisenberg and Bohr discussing Heisenberg’s manuscript.

This chapter synthesises the broad picture that emerges from Irish constitutional proeprty law about the mediation of property rights and social justice, and about the impact of progressively framed constitutional property guarantees on that mediation. It highlights the rewards for progressive property theory of doctrinal analysis and a wider comparative lens. Most fundamentally, it emphasises the political nature of constitutional property law in two ways. FIrst, judges gravitate away from innovative interpretation and application of ideas like social justice towards deference to the determinations of the elected branches of government. Second, constitutional property law can have political, and wider cultural effects, that do not reflect the strict legal effect of constitutional property rights as reflected in doctrine. It concludes that Irish constitutional property law demonstrates the challenges of implementing progressive property ideas in legal doctrine, but at the same time provides an illuminating example of a broadly coherent and effective attempt to implement a progressive constitutional structure for achieving partial resolutions of the tension betwene property rights and social justice.

This introductory chapter raises two questions that will guide us through the book. First, what does it mean to say that IHL ‘accounts for’ military necessity? Second, to what normative consequences does IHL accounting for military necessity give rise? The chapter offers the reader a mental roadmap of the discussions ahead. It also highlights the various tenets of inclusive legal positivism upon which the subsequent chapters are built.