# Bohr, QBism, and Beyond

## TL;DR

This paper explores the philosophical connections between Bohr's and QBism's interpretations of quantum mechanics, emphasizing their shared Kantian roots and addressing profound mysteries about consciousness and reality through a philosophical lens.

## Contribution

It clarifies the philosophical relationship between Bohr's ideas and QBism, revealing their shared Kantian influence and addressing fundamental questions about consciousness and reality.

## Key findings

- Bohr's philosophy aligns with Kant's transcendental ideas.
- QBism and Bohr share deep philosophical affinities.
- Philosophical insights from Upanishads inform quantum interpretation.

## Abstract

QBism may be the most significant contribution to the search for meaning in quantum mechanics since Bohr, even as Bohr's philosophy remains the most significant revision of Kant's theory of science. There are two ironies here. Bohr failed to realize the full extent of the affinity of his way of thinking with Kant's, and QBists fail to realize the full extent of their agreement with Bohr. While Bohr's discovery of contextuality updates Kant's transcendental philosophy in a way that leaves the central elements of the latter intact, Kant's insight into the roles that our cognitive faculties play in constructing physical theories can considerably alleviate the difficulties that Bohr's writings present to his readers. And while throwing a QBist searchlight on Bohr's writings can further alleviate these difficulties (as well as reveal the presence in them of the salient elements of QBist thought), Bohr's writings can in turn provide answers to important questions that QBism leaves unanswered (and also allay some of QBism's excesses). In the final sections I confront the two most impenetrable mysteries yet unearthed: making sense of quantum mechanics, and the dual mystery of making sense of (i) the existence of consciousness in a seemingly material world and (ii) the existence in consciousness of a seemingly material world. Here the relevant arguments are framed in the context of the philosophy of the Upanishads, according to which we (as Schr\"odinger put it) "are all really only various aspects of the One." There is no world that exists out of relation to consciousness, but there are different poises of consciousness. In particular, there is a poise of consciousness peculiar to the human species at this point in time, and there are poises of consciousness that are yet to evolve (and that may be essential to averting the calamities towards which humanity appears to be heading).