Is everything conscious?

Philosophy often seeks to make the world intelligible by providing explanations that render facts not arbitrary but inevitable. This idea is central to the work of German polymath Gottfried Wilhelm Leibniz (1646–1716) and Dutch philosopher Baruch Spinoza (1632–1677), who argued that every fact must have a sufficient reason for why it exists and why it is the way it is. For example, the mathematical fact that one plus one equals two is not just true but unavoidable once understood. Leibniz and Spinoza believed that philosophy’s role is to uncover these reasons, making reality comprehensible and meaningful. This aspiration is described by US philosopher Michael Della Rocca as the 'perennial hope and promise of philosophy', aiming to show that the world and our place in it are not random but structured by reason.

Panpsychism is the idea that consciousness is a fundamental property of all matter, meaning everything—from electrons and protons to tables, planets, humans, and dogs—has some level of consciousness. This challenges the common view that only humans and animals are conscious, while objects like rocks or chairs are not. For instance, while hitting a desk in frustration is morally acceptable, hitting a conscious being is not. Panpsychism rejects this division, proposing that even simple particles possess a rudimentary form of experience. This view is motivated by the desire to make the world intelligible, as it avoids the mystery of how non-conscious matter could suddenly become conscious in complex systems like brains.

The principle of sufficient reason (PSR) states that every fact or event in the universe has a reason or explanation for why it is the way it is, rather than some other way. This principle is foundational to Leibniz’s philosophy, where he wrote, 'there is nothing without a reason.' It also appears in the works of ancient and medieval philosophers like Parmenides, the Stoics, Thomas Aquinas (1225–1274), and the Islamic philosopher Ibn Sīnā (Avicenna, 980–1037). In modern philosophy, versions of the PSR are defended by thinkers like Shamik Dasgupta and Eddy Keming Chen, who argue that every fact in the universe is entailed by the laws of nature. For example, the mass of a proton (1.672 × 10⁻²⁷ kg) or the existence of the Chicxulub crater in Mexico (200 km wide, 1 km deep) must have a reason for being as they are.

The PSR implies that if every fact has a sufficient reason, then everything in the universe is necessary, meaning it could not have been otherwise. This view, called necessitarianism, is embraced by Spinoza, who argued that reality is a single infinite substance (God or nature) where everything is interconnected and inevitable. However, this raises concerns about free will, as it suggests that all events, including human actions, are predetermined. Critics like David Hume (1711–1776) and modern Humeans reject necessity, arguing that the world is simply a collection of unrelated facts without deeper explanations. Humeans, such as David Lewis (1941–2001) and Bas van Fraassen, contend that science can function without assuming universal necessity, focusing instead on observable patterns.

The hard problem of consciousness, coined by philosopher David Chalmers, asks why and how physical processes in the brain give rise to subjective experience. For example, why does the arrangement of matter in a human brain produce the feeling of seeing the color red, while the same matter arranged differently (e.g., in a rock) does not? This problem is 'hard' because scientific explanations, which describe objective, third-person facts, cannot account for first-person experiences like pain, joy, or the taste of chocolate. Chalmers argues that even a complete physical description of a brain leaves out the essential aspect of what it feels like to be conscious. This gap suggests that consciousness may not arise from physical processes alone, challenging traditional scientific approaches.

Panpsychism offers a potential solution to the hard problem of consciousness by proposing that consciousness is a fundamental property of matter itself. If electrons, protons, and other particles possess some form of rudimentary consciousness, then the emergence of complex consciousness in humans and animals is not mysterious—it is simply a combination of these fundamental properties. This view avoids the explanatory gap between non-conscious matter and conscious experience. For example, Leibniz suggested imagining a brain enlarged to the size of a mill: even if we could observe all its parts, we would not see consciousness emerge, as it is already present in the fundamental components. By making consciousness a basic feature of reality, panpsychism aligns with the PSR by providing an explanation for why we are conscious.