Black hole complementarity is an influential set of ideas that respond to the black hole information paradox. Unpacking this literature, I argue that black hole complementarity is about the consistency of quantum characterizations of an evaporating black hole and I delineate two consistency claims—i.e., two principles of black hole complementarity: operational complementarity and descriptive complementarity. A series of thought experiments in the physics literature on black hole complementarity gives us strong reasons to adopt the operational principle and reject the descriptive principle. Consequently, if we can stomach operationalism, then operational complementarity may suffice to resolve the black hole information paradox.

Astronomy shares many similarities with historical sciences: the reconstruction of token events, the lack of manipulation, and the reliance on traces. I highlight two benefits of viewing astronomy as a historical science. First, the methodology of historical sciences constitutes a more sufficient description of how astronomers study token events and regularities. Second, how astronomers identify traces of past events offers a more delicate understanding of what traces are. The identification of traces is only gradually achieved through iterations between data-driven approaches and theory-driven approaches, together with the cross-validation between multiple relevant historical events and between diverse datasets.

In this paper, we assess the extent to which contemporary observations of black holes---particularly those of the LIGO-Virgo and Event Horizon Telescope Collaborations---are ``theory laden''. General relativistic assumptions enter into the methods of both experiments through the use of simulations of black hole spacetimes. This includes numerical relativity simulations in the case of LIGO-Virgo and general relativistic magnetohydrodynamic simulations in the case of the Event Horizon Telescope. We argue that simulations play an ``ampliative'' role in both experiments, and that this role is problematically circular in the former case, but not the latter.

The spin-2 view on GR has been extremely influential in the particle physics community, including for the development of string theory. Leaving no doubt on its heuristic value, we argue that a foundationalist spin-2 view of GR, as often tacitly taken up as well, runs into a dilemma: either the spin-2 view is physically incoherent, or it leads to an absurd multiplication of alternative viewpoints on GR — in an immediate clash with accepted standards of theorising, and current knowledge of (quantising) gravity.