1. The Question of Consciousness
This essay is part of a longer attempt to think about consciousness after losing my 48-year-old husband, the philosopher Anand Vaidya, in 2024. I know he is gone. Yet there remains a stubborn sense that reality is somehow misaligned, as if what I can state with certainty and what I continue to feel have not yet agreed on the same world.
Unlike Anand, I am not a philosopher. In our discussions, he’d often reformulate my poorly articulated ideas into a rigorous argument. He was uniquely generous in spirit and action, brimmed with ambitious plans, sought authentic engagement above all things, and possessed a singular capacity for genuine affection for the numerous people in his orbit. That he is gone feels almost inconceivable.
The dominant view in analytical philosophy of mind is “physicalism” which posits that everything in the universe is physical or based on physical systems (no extra stuff needed). All causes and effects are physical in nature (including mental events), and all knowledge claims must be verified with a demonstrable, repeatable experiment. A caveat is that entire modern fields fall within this vaunted circle, despite their claims being “validated” by purely statistical methods that repeatedly fail replicability (for example, the fields of psychology and medicine). My undergraduate degree is in physics, and I understand the attraction of physicalism, even as I grow increasingly skeptical that it is true.
While physicalism is now broadly taken to be the default position, whether anything lies outside the purview of physics has been the crux of much philosophical discourse since the dawn of what is now called “modernity” in 17th century Europe. This “anything” was often discussed in the context of theism, and I will therefore use “God” as shorthand for it, with the understanding that we are talking about some quality or quantity that stands outside the realm of the physical.
One of the foundational notions of philosophy, that I will also draw from, regards the role of intuitions to advance philosophical inquiry as described by Newton’s older contemporary, the French polymath René Descartes (1596 - 1650), who is credited with birthing the modern field of epistemology with his 1641 work Meditations on First Philosophy. Wrote Descartes in the posthumously published Rules for the Direction of the Mind: “By "intuition" I understand, not the fluctuating faith in the senses, nor the false judgment of badly constructed imaginings, but the conception of the pure and attentive mind which is so simple and distinct that we can have no further doubt as to what we understand.”
The precursors to physicalism included “materialism” with a similar commitment to the idea that all can be described by physical systems (including mental phenomena). The English philosopher Thomas Hobbes (1588 - 1679) ascribed to a materialist position, famously applying it to political philosophy and human nature in Leviathan (1651), even while allowing for God as “first cause”. His fellow Englishman, Robert Boyle (1627 - 1691), whose Boyle’s Law describing the behavior of ideal gases is still staple of physics today, also ascribed to materialism, but one where nature followed God’s rules.
However, what accelerated the idea that “all is physics” to broad acceptance was the work of Isaac Newton (1643 – 1727). Prior to Newton, epistemology was dominated by scholastic methods that relied on Aristotelean methods of argument (or rationalist deduction as deployed by Descartes) to prove or disprove hypotheses. Post Newton, the British empiricists increasingly claimed epistemology as synonymous with empiricism, while the one-time “queen” of philosophical inquiry, metaphysics, fell into near irrelevance, as noted later Immanuel Kant (1724 - 1804) who, with his seminal 1781 work Critique of Pure Reason, mounted a sort of comeback for the field.
Anand might have found my selections on which philosophers to focus on here, somewhat arbitrary. In response I will only say that the amount of material written on the topic is so voluminous that any attempt to distill it will likely lead to choices that feel arbitrary, eventually even to the writer.
With that, I will begin by briefly summarizing what I understand to be Anand’s views on consciousness, both to serve as an overall view of what contemporary philosophers of mind and consciousness think about, and because it is to him that I dedicate these explorations.
I will reiterate that I am not a philosopher by training, nor does this essay pose as exhaustive primer to the topic of consciousness. This work is best viewed as a personal undertaking to understand the nature of the mysterious thing that grounds my grief.
2. A Very Brief Snapshot of Anand Vaidya’s work & Contemporary Discussions of Consciousness
The overwhelming consensus among philosophers of mind today is that consciousness can be explained in terms of physical events in the brain and body such as neurons firing, synapses exchanging signals, and networks in the brain behaving in a self-organizing manner. In this view, the conscious mind just is whatever information processing activity the brain carries out, just as digestion is what the stomach does. However, philosopher's critical of physicalism point out a persisting explanatory gap: no description of neuronal activity, however detailed, explains why such activity should be accompanied by experience. This is the “hard problem” of consciousness, as David Chalmers coined it in “Facing up to the problem of consciousness” (1995): why is it like something to be a brain, and not simply the functional execution of tasks?
Even if we take physicalism to be true, questions arise as to how that could be, and it is to these questions towards which intense interdisciplinary labor is now devoted. For example, when does consciousness begin and end? Is it flickering in and out in sleep, in coma, in meditative absorption? Can we draw a line between the unconscious and the conscious? This approach, as articulated by Giulio Tononi’s 2004 paper “An information integration theory of consciousness” led to the hunt for “neuro-correlates” of consciousness, viz empirically measured processes that could be tied to a “threshold” for what counts as conscious phenomena. Another approach to explaining the physical basis for consciousness was put forward by Stuart Hameroff and Roger Penrose’s 1996 “Orchestrated Reduction of Quantum Coherence in Brain Microtubules: A Model for Consciousness” that favors consciousness as arising from quantum neuronal processes in the brain.
Anand’s work connected classical Indian theories with contemporary debates in analytic philosophy, even while he suggested that they took different approaches: “While the mind-body problem is prominent in Western philosophy of mind after Descartes, in Indian philosophy the primary problem is over how consciousness is related to the mind-body complex, since the mind (manas, buddhi) is often taken to be inert and part of nature (prakrti).”
As a solution to the hard problem, Anand favored the idea that consciousness is “fundamental”, that it is to say it is basic and irreducible, not grounded or rooted in other stuff like the physical. This is pertinent in “panpsychist” theories in contemporary Western philosophy, which hold that besides being fundamental, consciousness is also ubiquitous, even in the natural (non-human) world. Panpsychism has deep roots in Western philosophy, stretching at least to the 6th century BC Ionian philosopher, Thales and it is currently undergoing a resurgence in popularity in analytic philosophy. Modern cosmopsychists like Philip Goff, for example, posit that the cosmos is conscious, while Galen Strawson has forwarded the view that consciousness is a fundamental constitutive (physical) property of the universe, like mass or charge. Modern panpsychists address the hard problem because by positing the fundamentality of consciousness, they do not need to explain its emergence from purely material processes.
Like modern panpsychists, Anand favored a fundamental role for consciousness, rather than merely an emergent or epiphenomenal one. However, his ideas were more aligned with Vedāntic illuminationism: consciousness is unlike any other thing; it is the necessary condition for the appearance of all objects.
Anand argued in favor of the realist view of the conscious self as articulated by the 11th century Indian philosopher, Rāmānuja. Anand was not an “illusionist” about the conscious self as advocated by Śaṅkara’s Advaita Vedanta. He writes: “Finally, to hold that the individual self, qua individual, is an illusion and the world that it experiences is an illusion is not acceptable to me. At least one reason is that this view requires a radical departure from ordinary metaphysics ... A revision of this kind is only justified given very strong evidence, something which I take to be lacking. Some might think that quantum field theory gives us reason to believe in illusionism about the material world we experience because it posits fields as fundamental and not, for example, material bodies. I am skeptical as to whether the best interpretation of quantum field theory requires us to hold that the ordinary world we experience is an illusion because fields are fundamental. Again, one can simply hold that there are different kinds of reality where both are equally real.”
He advocates for an approach that sifts out illusions, rather than beginning with a description of fundamental reality: “What is important to me is discovering different kinds of illusions in our experience and isolating what is not an illusion, in a gradient view of reality.”
3. The Seventeenth-Century Revolution
3.1 Descartes, Newton, and Locke: Dualism, Mechanism, and Representation
The 17th century was one of the most consequential, perhaps the most consequential, for the field of epistemology. First, in Discourses on the Method (1637) and Meditations on First Philosophy (1641) René Descartes argued that the world appears to be fundamentally separated into two kinds of things, viz mind (the essence of which is thought) and matter (the essence of which is extension in space). Then, by questioning all beliefs that could possibly be false, including sensory perceptions and mathematical truths, under the hypothesis of an evil demon deceiving him, he arrives at the realization that even if he is being deceived, he must exist to be deceived. This led to the insight: “I am, I exist, is necessarily true whenever it is put forward by me or conceived in my mind” as encapsulated by his famous maxim: cogito ergo sum. Meditations also offered a proof of the existence of God.
Almost five decades later in 1687, Isaac Newton shattered the epistemological world by laying out his theory of gravity and laws of motion in The Mathematical Principles of Natural Philosophy. Prior to Newton, the scholastic tradition that focused on argumentation to arrive at truth (in the manner of Meditations) was the primary method of epistemological discourse. Post Newton, that changed. The enormous impact of Newton’s work on European thought was captured by Newton’s Genesis-evoking epitaph as written by the translator and poet Alexander Pope (1688 - 1744): “"Nature and nature's laws lay hid in night; God said 'Let Newton be! ' and all was light."
It was within this time of epistemological upheaval that John Locke (1632 - 1704) published An Essay Concerning Human Understanding (1689). Locke had become closely associated with the newly ascendent “scientific method” and is considered a father of empiricism.
Like Newton, Locke believed in the idea of a “mechanical” universe, one that had been put into motion by a divine creator. Unlike Newton, however, who focused on what was called “natural philosophy” at the time, Locke’s primary interests were as statesman, his work aimed at influencing the policies being enacted by the politically powerful in his orbit. Locke’s writings profoundly inform “modernity”; to cite just one example, his work singularly influenced the authors of the U.S. Constitution (including Jefferson and Madison's emphasis on natural rights and limited government).
Alexander Campbell Fraser in his 1894 introduction to On Human Understanding writes that Locke took on the essay as there is “nothing more absurd than to argue about the mysteries of the universe without consideration of the relative competency of the mind of man.” At the end of such consideration, Locke advanced a version of the “representationist” thesis: our perception of the “world out there” is “represented” as ideas in our mind.
For Locke, the properties of what is really out there are “primary” (e.g. size, shape, motion) while the qualities we perceive through our sensory organs and what our mind ideates, he calls “secondary” (e.g. color, sound, smell). These mental representations are not real in the sense that they are comprised of secondary, rather than primary, qualities, but are nevertheless representative of mind-independent objects that exist in reality. Given our sensory organs are fitted to serve an organism with human dimensions, we accurately perceive things roughly our size, too coarse for the microscopic, too limited for the cosmic, what we take to be the real quality of things will be thus, at best, incomplete.
The physical pattern in the brain is distinct from the mental idea which, according to Locke, is how the physical pattern in the brain is “represented” by the mind as mental phenomenon. For Locke, what is “really out there” is comprised of “insensible” atoms that act on “impulse”. The primary qualities of the “substance” of the things that make up the world would remain forever unknowable. The only thing we can ever truly know is the representation of an idea in our minds, given there “is no discoverable connection between any secondary Quality, and those primary Qualities that it depends on.”
Locke differentiates mental phenomena as distinct from the things composed of “corpuscular” atoms, and so would not be considered a “physicalist” in the modern sense. He offers, however, that he does not have a basis in that belief, and concedes that it may yet be found that there is only one kind of thing in the world, which may be material.
3.2 George Berkeley: Radical Idealism and “To Be Is to Be Perceived”
George Berkeley’s (1685 - 1753) radical idealism arose primarily in opposition to empiricism. In De Motu (1721), he proceeds by examining core metaphysical ideas, summarily dismissing each one as nonsensical, before advancing his own theory. Thus:
Definitions as bug, not feature: “So very true it is that definitions, as they shed light on some things, in turn shroud others in darkness. And indeed, anything we perceive by sense could hardly have been made clearer or better known by any definition. Enticed by the vain hope of doing this, philosophers have rendered easy things difficult, and entangled their minds in difficulties, which for the most part they themselves have engendered.”
The Greeks: “The contemplation of motion remarkably troubled the minds of the ancient philosophers, from which various exceedingly difficult (not to say absurd) opinions originated, which have now almost fallen into obscurity and so hardly merit that we should dwell upon discussing them in much detail.”
He initially aligns with Descartes on basic dualism: “There are two supreme classes of things, body and mind. We know by sense something extended, solid, mobile, figured, and endowed with other qualities which meet the senses; but we know by a certain internal consciousness the sentient, percipient, intelligent thing.”
But he refutes Descartes’ assumption that matter is distinguished by "extension" in space. Descartes’ thought experiment that led to “cogito ergo sum” is repurposed; he uses a similar imaginative doubt to show that "space" reduces to relational absence, not a real entity (anticipating Mach and Einstein's relational views of space). Ultimately, "whatever is predicated of pure and absolute space can as well be predicated of nothing," from where he then argues “By this reasoning the human mind is most easily freed from great difficulties and from the absurdity of attributing necessary existence to any thing beyond the good and great God alone.”
Thus, Berkeley’s response to Locke’s view that mental phenomena are "secondary" and merely representative of the “primary” qualities of the external world was to deny the mysterious material substance altogether. He posited that empirical coherence across subjective minds stems from divine oversight, to put it another way, for Locke, God was the "ghost in the machine" of reality.
His argument goes something like this: (1) Locke was right that reality is represented as ideas in the mind; (2) Given the coherence in most minds' representations, some guiding force must exist; (3) This force must be omniscient, eternal, and benevolent to ensure order over chaos; (4) That force can only be God.
Still, he concedes physics has practical value, even if not for revealing true ontology: "… to be of service to reckoning and mathematical demonstrations is one thing, to set forth the nature of things is another." Scientific theories are useful, but not factual.
In A Treatise Concerning the Principles of Human Knowledge (1710), Berkeley further equates perception with existence itself in his famous third principle of knowledge: “To be is to be perceived” or in Latin “esse est percipi”.
Berkeley (1) rejects absolute space/motion and (2) argues that unperceived things don't exist independently of perception (by finite minds or God's infinite one). Thus, Berkeley’s mission of making God central to the discussion was achieved, but at the cost of denying the existence of matter.
3.3 David Hume: Radical Skepticism and the Dissolution of Causality
Berkeley’s contemporary, the English philosopher David Hume (1711 - 1776), published An Enquiry Concerning Human Understanding (1748), (recalling the title of Locke’s famous On Human Understanding). Hume, as staunch empiricist, aimed to refute Berkeley but by carrying Berkeley’s radical idealism further into radical skepticism.
Even that unimpeachable foundation of physics, the principle of causality, is not immune to skeptical inquiry: “Similar objects are always conjoined with similar. Of this we have experience. Suitably to this experience, therefore, we may define a cause to be an object followed by another and where all the objects similar to the first, are followed by objects similar to the second. Or, in other words, where if the first object had not been, the second never had existed. The appearance of a cause always conveys the mind, by a customary transition, to the idea of the effect.”
(1) He agreed with Berkeley (and Locke) that one can never know the nature of the “substance” out in the world; the entirety of what we can claim to know consists of individual, momentary perceptions (thoughts, feelings, sensations).
(2) The notion that a persistent conscious self exists based on these momentary perceptions is based on the principle of causality; we see a billiard ball hit another and assume that the second moved because of it, but all we can really be said to know is a correlation of two actions, that one caused the other is what he called a “belief” generated from repeated observation. Likewise, the stitching together of momentary percepts into a persistent, conscious self is not based on reasoning or experience of necessary connection, but based on the habitual belief in causality. Take away causality and the belief in a persistent, conscious self is unjustified.
(3) Further, we can never “know” that the mental phenomena occurring in another’s mind coheres with our own, indeed, while we take mental phenomena exists in other minds, we cannot know it.
(4) Therefore, God is unnecessary as causal factor, including as benevolent mediator that allows for mental phenomena in minds cohering, as per Berkeley.
Hume carried empiricism to morality, arguing that if we cannot know anything about physical reality, then then is even less hope for morality: “The great advantage of the mathematical sciences above the moral, consists in this, that the ideas of the former, being sensible, are always clear and determinate … But the finer sentiments of the mind, the operations of the understanding, the various agitations of the passions, though really in themselves distinct, easily escape us, when surveyed by reflection.”
3.4 Immanuel Kant: Transcendental Idealism and the Postulates of Practical Reason
Before Immanuel Kant wrote his monumental 1781 work, Critique of Pure Reason, his interest was in “natural” philosophy that attempted to describe the motion of heavenly objects, among other works. He bemoaned that Metaphysics, the onetime “queen” of philosophical endeavor had fallen into irrelevance, “Why is it, then, that in metaphysics we have thus far been unable to find the secure path of science? Might this path be impossible here? Why, then, has nature inflicted on reason, as one of reason’s most important concern, the restless endeavor to discover that path?”
In Critique of Pure Reason, Kant argued “transcendental” idealism; he separated “noumena” the intrinsic nature of things or “things in themselves” from “phenomena”, or things like they appear to us, without denying the existence of either. “Transcendental”, as Kant uses the word, does not carry mystical overtones, he means it in the sense of “necessary prerequisites”; our intuitions about space and time are “a-priori” or a necessary prerequisite for experience, as all experience is spatiotemporal. Likewise, the conscious self is “transcendent” in that without it, we would experience only an incoherent stream of sensory data. This “transcendence” extends to mathematical structures. Geometry, for example, is based on our a priori (necessary prerequisite) intuition of space. We know Euclidean stuff like "the shortest path between two points is a straight line" without measuring the world because space is a mind-imposed structure.
Kant also became renowned for his moral philosophy. His famous Categorical Imperative in Groundwork of the Metaphysics of Morals (1785) holds that a good will, acting from duty, not inclination, is the only thing good without qualification: “Act only according to that maxim whereby you can at the same time will that it should become a universal law." Notably, the Categorical Imperative presupposes freedom: only a being capable of self-legislation can be bound by moral law. While empirical causality governs the phenomenal world, freedom allows rational beings to act as noumenal “first causes” in moral decisions, initiating actions outside the deterministic chain of natural laws.
In Critique of Practical Reason (1788) Kant argues that moral law is grounded in “pure practical reason” and God’s will is good because it conforms to moral law. His argument goes something like this: We are rational beings. Through reason alone, we discover the Categorical Imperative. This Categorial Imperative is objective, universal, and binding. It commands duty unconditionally, and actions done from duty possess moral worth. However, “pure practical reason” must be systematically coherent. It cannot rationally command us to pursue virtue while knowing that virtue could lead to misery without resolution. In the observable world, virtue and happiness do not always align, creating an antinomy (logical impasse). Therefore, reason demands we postulate the possibility of the “Highest Good” that will eventually balance the ledgers so that the greatest virtue is rewarded with the greatest happiness. So, to make the Highest Good possible (not proven, but rationally pursuable), we must postulate immortality and God as supreme, rational, moral cause who ensures that happiness is eventually distributed according to moral worth because reason demands justice.
Kant’s work on epistemology and metaphysics that struck a balance between empiricism and idealism anticipated the “new physics” that would once again force a radical revision of what we thought we knew about the nature of fundamental reality. I’ll note briefly here that Anand’s dissertation, The Epistemology of Metaphysical Modality (UCSB, 2005) drew extensively on Kant’s work.
Conclusion to Part I
So dawned the 19th century. Newtonian mechanics had conquered Physics and physical theories that described predictably repeatable behavior were being applied to real-world solutions. Kant’s Transcendental Idealism favored empiricism as epistemology (with a dash of idealism in the form of necessary pre-requisites) and his Categorical Imperative offered an elegant way of thinking about morality. Epistemology and metaphysics were, if not solved entirely, practically so. But then arrived a tsunami in the form of the “new physics”: the theories of relativity and quantum mechanics, that would once again upend everything we thought we knew about how the world worked and reopen the door to views like Anand’s that challenge the dominance of physicalism.
