What is Physical? – Crumbling Physicalism

When Physical Became Synonym with “You’ve Got to Take This Seriously”

Full script:

First Part:

Physicalism: the ontological thesis that everything is physical or that the real world consists only of physical entities. In other words, physicalism is the position that everything which exists is no more extensive than its physical properties, that there are no kinds of things other than physical things. From the physicalist world view, all phenomena – including thoughts, feelings, emotions, consciousness and intent – can be explained in terms of physical interactions.  

Note that, nowadays, the term physicalism is still used interchangeably with materialism by many people. Personally, I like to make a distinction between these two world views, although the distinction is mostly based on historical factors. If you have not watched it yet, you may want to watch my previous video titled “The Fall of Materialism”, also available from my channel. In addition, note that physicalism is also commonly associated with an entire package of other metaphysical views and methodological doctrines – such as reductionism, causal closure, empiricism or atheism, for instance. In this video I will NOT cover any of these other associated views; I will just cover physicalism, in the way it was previously defined.

So it is pretty obvious that the big question we need to answer here is… What do we mean by physical? Is physical just all of that which we can directly measure with our instruments? Or does the term physical also extend to other theoretical entities which may not be directly measurable, but nevertheless entities which have more or less become accepted within mainstream science? But is it wise to constrain our definition of physical, natural or real to just those things which we can directly measure with our instruments or to just those things which are currently being modelled by our most popular scientific theories?

And what qualifies as a measuring instrument, anyway? Is human consciousness a valid instrument? Is consciousness itself physical? Is it sensible to consider all those things which we cannot measure with our material instruments or which we cannot currently explain in known physical terms, as not real, not physical or to mockingly call them imaginary or supernatural? How about all those things we cannot measure directly but which can still produce consistent, indirect measureable effects? Are those things real? Are they physical? Are they natural?

In this video, more than aim to answer any of these questions, I will aim to shine some light onto the fact that, most of the time, the physical vs non-physical, the natural vs supernatural, or real vs not real discussion is, in my opinion, a complete waste of time. It is much wiser to take a step back from any ideologies or metaphysical ontologies we may subscribe to or feel identified with, and realise that getting hung up on definitions is not only limiting but completely unproductive. It is much wiser to remove our attachment from terms or labels which today, for all intents and purposes, have been rendered practically meaningless, as it becomes evident for instance, when we take into consideration the latest discoveries and theories being developed in modern physics.

The way I see it, a great part of the problem stems from the fact that we all tend to get a bit too attached to creating clearly defined boundaries, such as  the one between "physical" and "non-physical", or between what is real and what is illusory,  between what is natural and what is supernatural, and so on. Each time somebody uses these words, it is usually within the context of a different metaphysical world view (such as physicalism, idealism or dualism) and hence why these terms often mean very different things to each of us, depending on the world view we might identify the most with.

The end result is that the words "physical" and "natural" have ceased to mean anything in particular. For instance, those who subscribe to physicalism, tend to use the word non-physical as synonym with supernatural, imaginary or not real… On the other hand, those who identify mostly with a dualistic worldview, tend to use the word non-physical as synonym with mental, non-material, or as synonym with all of that which exists separately from the physical. Finally, those who feel more identified with idealism, see the physical and non-physical realms as being part of the same unified whole, which is seen as being fundamentally mental by nature.

So, upon close examination, it becomes quite clear that "physical" is actually a rather ambiguous and abstract term with no defined ontological basis, it is ultimately just semantics, a changing concept that is evolving in the same way that our culture and our scientific discoveries and models are evolving. It is a term that no longer serves us any purpose.

I like how Noam Chomsky’s talks about this issue. He says:

"The term physical is just kind of like an honorific word, kind of like the word 'real' when we say 'the real truth'. It doesn't add anything, it just says 'this is serious truth'. So to say that something is 'physical' today just means 'you’ve got to take this seriously'. […] As soon as we come to understand anything, we call it ‘physical’ " Noam Chomsky, Linguist, Philosopher & Cognitive Scientist

It seems to me that we have become so obsessed with creating well-defined conceptual boundaries, that we are so used to creating clearly delineated categories of understanding, that we end up forgetting about the high level of abstraction implicit in the creation of these boundaries or categories. Not only we create unnecessarily rigid conceptual boundaries but we then proceed to equate these purely conceptual barriers with real existing barriers which we think divide ontologically distinct realities, a process which obviously leads to catastrophic consequences.

Anthropologist Mary Douglass talks about this in her book Purity and Danger. She writes:

“Powers are attributed to any structure of ideas. The yearning for rigidity is in us all. It is part of our human condition to long for hard lines and clear concepts. We have to either face the fact that some realities elude them, or else blind ourselves to the inadequacy of the concepts.” Mary Douglas, anthropologist, author of "Purity and Danger"

The erection of all of these rigid conceptual barriers inevitably contributes to our struggle in explaining how such different things can possibly interact with one another. We fall into the dualistic trap. We are baffled by questions such as how can something non-physical ever interact with something physical? How can something as immaterial as mind interact with something as physical as the material body? Or… How can a wave function, a mathematical abstraction operating in an abstract space, possibly have a real effect on the physical world?

Mainstream science has tried to stay away as much as possible from the dualistic trap by subscribing to materialism, or more recently, by subscribing to physicalism, otherwise called naturalism. As the definition of matter has become more and more ethereal, and as entities such as immaterial fields, space-time, virtual particles, black holes or parallel universes are being discussed within science as real existing entities, classical materialism has had to inevitably evolve into something which can potentially accommodate all sorts of weird abstract entities. And the irony of it all is that we are currently utterly unable to directly measure most of these abstract entities.

I like how Alan Wallace touches on the problem of defining the physical world. He asks:

“What is the Natural world? Many people equate it with the physical world… So we’ve got physical space, time, matter, energy… That pretty much well should do it, right? The problem with ‘physical’, is the very notion of the category, because the category of the ‘physical’ is a moving target, and it is moving now. A crucial element here that is often overlooked is that the demarcation between physical and non-physical is created by human beings. Nature didn’t whisper into the ear of a physics department at MIT ‘this is the real definition’! Is a probability function physical? Is a mathematical description of an electromagnetic field physical? Is dark matter physical? How about dark energy? How about the laws of physics? So what does the word physical even mean anymore? What we know is it’s become very ethereal and what we know is there is no consensus.” – B. Alan Wallace, physicist & philosopher, author of “Hidden Dimensions” & “Meditations of a Buddhist Skeptic”

It is quite obvious that, when viewed from a historical point of view, this process highlights our desperate attempts to re-establish our position as being the most rational and scientific while at the same time having no other option than to expand our rigid and outdated world views to the study of phenomena which not only defy our notions of what is physical, but to the study of phenomena which in fact defy our very notion of what lies within the scope of science since some of these phenomena are well beyond the scope of our scientific method, as it is currently formulated. For instance, consider the idea of parallel universes or extra dimensions and any theories which assume the existence of such entities.

This transformation of materialism into physicalism is nothing but our attempt to re-establish some clearly defined boundaries between what we consider likely to exist and what we don’t, between what we think is describable in terms of physical laws and physical models and what we think is not, funnily enough, independently of whether the scientific method is currently applicable to the study of our theorised entities or not. We can’t deny that this pysicalisation process of reality is just crumbling; the boundaries are not only expanding quicker than ever before, but in fact they seem to be completely dissolving before our eyes! Perhaps the most important thing is that we realise that it is precisely our beliefs, prejudices and dogmatic attitudes which are the biggest obstacles when it comes to breakthroughs within science. That it is mostly our own rigidity that is getting in the way.,,,

“No part of the aim of normal science is to call forth new sorts of phenomena; indeed those that will not fit the box are often not seen at all” Thomas S. Kuhn

For instance, consider the field of study involving ESP or mind-matter interaction. Often, it is simply because we don’t believe that certain woo-woo phenomena exist, or simply because we belief there is not enough evidence to support their existence, the only reason we cannot possibly grant these supernatural things the honour of being thrown into the supreme category of the physical, the category of phenomena we are prepared to take seriously enough. It is usually more of a question of beliefs and prejudice than anything else.

“After studying these phenomena through the lens of science for about 30 years, I've concluded that some psychic abilities are genuine, and as such, there are important aspects of the prevailing scientific worldview that are seriously incomplete. […] those who loudly assert with great confidence that there isn’t any scientifically valid evidence for psychic abilities don’t know what they’re talking about. […] the hysterical rants one finds in various online "skeptical" forums appear to be motivated solely by fundamentalist beliefs of the scientistic or religious kind” – Dean Radin, Chief scientist at IONS, Author of “The Conscious Universe”, “Entangled Minds” & “Supernormal”.

The fact of the matter is that, from a rigid physicalist perspective, the core of the problem is not going away. Think about the mind-body problem for instance. Your consciousness, your own subjective experience, your thoughts, your emotions, your conscious intent… None of these seem to have any of the attributes of what we call a physical thing (such as charge, mass, location, momentum and so on). And they can’t be measured directly with our instruments either – since by their nature they are only experienced in the first person – nor can they be said to follow or emerge from any known physical laws…. Surely they can’t be called physical by any conventional meaning of the word! And yet, what else could they be if one views the world from a narrow physicalist perspective?

Does this mean that we are forced to deny their existence simply because they do not fit into the physicalist world view, hence ending up in the territory of eliminative materialism?

“Consciousness is an illusion of the brain, for the brain, by the brain.” Daniel Dennett, Philosopher and Cognitive Scientist, author of “Consciousness Explained”

“It’s pretty clear that there is only the physical brain. […] There is no non-physical mind, soul or spooky stuff.” Patricia Churchland, philosopher, author of “Touching a Nerve”

Or does this mean that – realising that denying their existence is perhaps somewhat silly – we are then forced to explain their existence only in terms of those entities we currently define as physical, thus often falling prey to reductive physicalism?

Reductive Physicalism: the view that claims that all psychological states of the mind (1^st person perspective) can be reduced to physical states in the brain (3^rd person perspective). This view allows for mental states, but these are assumed to be explicable in purely physical terms by observing the correlated brain states.

Eliminative Materialism: a much stronger view than reductive physicalism. In its strongest form, it denies the existence of any sort of mental states. To eliminative materialists there are only physical states.

Or… if we still feel we can’t possibly allow ourselves to completely let go of physicalism just yet, how about this other option … Maybe we can somehow expand our physicalist world view to make it compatible with the concept of emergence?

Non-Reductive or Supervenience Physicalism: the view which claims that all non-physical properties in the world metaphysically supervene upon the physical. If all non-physical properties in the actual world metaphysically supervene upon the physical, then there cannot be a world that is just like ours in all physical respects, but which differs from ours in some non-physical respect. Supervenience physicalism has been seen as a form of emergentism, in which the subject’s psychological experience is considered genuinely novel. While some forms of emergentism appear either incompatible with physicalism or equivalent to it, others appear to merge both dualism and supervenience.

Still, emergence doesn’t seem to solve the core of the mind-body problem, it doesn’t solve the hard problem of consciousness…

“You are a different kind of experience – a different quality of experience – when you see red, when you see green, when you hear middle C, when you taste chocolate… Whenever you are conscious – whenever you have a subjective experience – it feels like something.”  David Chalmers, Philosopher and Cognitive Scientist (who coined the terms “hard problem of consciousness”)

So how about I tell you what my favourite option is? If a problem is so persistent and difficult to solve that it simply refuses to go away from the perspective of the physicalist world view, would it not be a wiser and more practical option to just try to let go of that world view altogether and start looking at things from a completely different angle, an angle where all the implicit assumptions of the physicalist worldview are not taken for granted anymore? Beliefs and assumptions that are so ingrained in our culture won’t be easy to let go of, but the time has come for a shift in perspective, and this shift cannot occur unless we make an effort to abandon our rigidity and resistance to change, unless we make an effort to abandon our prejudices and really open our minds to alternative world views.

Second Part:

Ok, now let me take you back to the problem with the definition of the physical world by using a couple of very interesting examples from the world of physics.

Let’s start with the quantum wave function. Ask yourself this question: is the wave function physical? Let’s examine this in detail… Well, a wave function is clearly our own abstraction, our own mathematical description of what Nature may be doing behind the scenes, when nobody is looking, when no measuring is taking place. In addition, we know that a wave function cannot be measured directly, it is an entity which describes a process taking place in an abstract space which has nothing to do with our familiar, everyday space-time. As Werner Heisenberg pointed out, the wave function can be considered to be representative of some sort of potential world which has not yet been brought into actuality. Therefore, in every possible sense of the word, if we analyse it carefully, it seems clear that the wave function is actually pretty much a non-physical thing…. It has no attributes whatsoever of what can be defined as physical, not to mention the fact that the wave function is something which cannot be measured!

Nevertheless, we can indeed say that the wave function does somehow seem to represent some sort of underlying process in Nature, and we can say this because the results of our quantum mechanical experiments agree with quantum theory to such a high degree of accuracy that we cannot escape the conclusion that the wave function is in fact describing a layer of reality which does indeed exist. Yes, the wave-function is just an abstract mathematical concept, but it does seems to describe some sort of behind-the-scenes reality, or at least some sort of process running in the background which has a direct relationship with what we ordinarily call the physical world.

Whether you want to call the wave function or the "space" it describes physical or non-physical is a just question of semantics. Personally, because the wave function is our own mathematical tool (it is an abstraction, an idea, a concept) and because it’s not directly measurable, I would say that the wave-function is non-physical. But, honestly, I think this is completely irrelevant. What’s important here is that we realise that the wave function does appear to describe a layer of reality beyond our familiar space-time which is indeed operationally real, a layer which is somehow linked to our familiar physical world, through the process of measurement, with observable effects which we can indeed measure within the confines of our own space-time.

Here’s another fascinating example. Take virtual particles, for instance. What do you think… Are virtual particles physical? As I explained in my previous video on materialism, these particles are postulated to pop in an out of existence all the time, out of nothingness, of out emptiness. Although in principle, these virtual particles cannot be observed, that is, they cannot be measured directly, the net effect of the quantum fluctuations in the vacuum associated with these particles has indeed been measured; and it turns out that this net effect has a magnitude which was very well predicted in advance:  it is called the Casimir effect.

The Casimir effect is related to the so-called zero-point energy, the energy of empty space, where virtual particles are postulated to pop in an out of existence in a continuous state of fluctuation. The experimental confirmation of this effect led to the process whereby virtual particles, despite being unobservable, gradually acquired the status of being considered to be real existing entities, given that that these entities did produce effects which were in fact measurable. However, real or not real, physical or not physical is beyond the question, because, remember, what we call virtual particles is just our own abstract conceptualisation of something we cannot directly measure. The point is that this conceptualisation is useful and it seems to describe a layer of reality, namely the vacuum, or zero-point field, a kind of emptiness filled with potentiality, which does indeed interact with our more familiar physical world.

Can you see what I am trying to show from these two examples? What is truly important is not whether something can be said to be physical or not. The distinction between physical and non-physical is created by us and therefore it is ultimately irrelevant. What’s important is not whether we can successfully objectify our postulated entities; because obviously, if anything has become evident with the advance of modern physics, is that the objectification, the conceptualisation, the physicalisation of reality is proving more and more elusive, as we dig deeper and deeper into the rabbit hole. We just have to get used to the fact that, nowadays, science has to constantly deal with abstract, unfamiliar, unobservable, unobjectifiable entities.

For all intents and purposes, all that we really want to know is whether these weird theoretical entities that we are trying to describe or understand produce any effects which are measurable. No matter how weird, counterintuitive, supernatural or impossible to conceptualise these entities appears to be, all that we should be concerned with is with finding out whether we can measure this thing directly, and if not, which is often the case, finding out whether we can indirectly measure their existence through the measurement of their effects.

I would like to finish this video with some of Tom Campbell’s thoughts, which I think summarise the essence of this video quite well. He explains how, as a physicist and as a keen consciousness explorer, he dramatically expanded his views on what can be considered real, independently of whether one perceives it as a physical thing or not. He therefore emphasises the importance of forgetting about the physical vs non-physical debate and stresses the importance of using the concept of operational functionality instead. Put another way, what we need to ask is: does this thing we are trying to study or describe produce any measurable effects, independently of whether the thing itself is directly measurable or not?

I particularly like the following passages, where he elaborates on these ideas using examples from the world of physics and also using the example of personal subjective experience. He writes:

“Up to this time, I believed that meaningful existence was confined to an operational reality. […] if something can be measured, it is real. To be measurable, a thing must interact with our senses or with some device that interacts with our senses. […] It was that simple; things were either operationally real or irrelevant. Things that are not measurable, but can be inferred from other things that are measurable, fall into the grey area of conjecture. All things theoretical or hypothetical fall into this grey basket. […]

The primary mission of the academic research scientist is to collect enough valid, repeatable, measurement data to transfer a grey theoretical construct into a real object or effect. […] quantum mechanical wave packets, black holes, quarks, justice, and love all fit into that grey area. […] With enough real measured data one might eventually move a thing, such as black holes for example, from the realm of the hypothetical to the realm of the real – but only with sufficient good quality data. That particular attitude has never changed. I continue to feel that way, work that way, and employ that methodology to sort out what is real from what is not.

But I had to change my philosophy of reality. There were those things that were non-measurable yet functionally operational (including my meditation state, which is properly defined as an altered state of consciousness) that fell into the category of subjective experience with objective results. One can use these non-measurable states of mind to operate on real things. […] My reality expanded […]

If a thing is well-defined and consistently functional, then it must also be real. How could something not real directly affect things that are real? By definition, in an operational reality, things that are not real have no measurable effect, cannot interact with, and have no relevance to, things that are real. […] Real things, significant things, must now be either objectively measurable, or consistently and predictably interactive with real things. That was a major expansion of my real world. […] Any credible conception of reality must include subjective experience that can consistently and universally lead to a useful objective functionality.”

Tom further expands:

“Most people are comfortable with the fuzzy notion that what we can directly measure is by definition physical and everything else is non-physical. This places two familiar groups of things into the non-physical camp: those that are inferred but not yet directly measurable (neutrinos for example) and those that are conceptual (such as wave packets, dark matter, strings in physics theory, as well as ego, love, ethics and justice). Inferred entities can only be indirectly measured by actually measuring something else that is assumed to be causally related. […]

Initially, conceptual entities are defined into existence (as were neutrinos or quarks) by our need for them to support and maintain the consistency of our current world view. Their operational functionality and their ability to help us maintain logical consistency is accepted as proof of their potential physical reality. […] They are operationally significant. That they are initially operationally non-physical (cannot be directly measured) only relegates their existence to the theoretical, not to the absurd. They are in the wings waiting for scientific experience to give them full membership into the world of the physically measurable – or at least into the world of things with physically measurable effects. Thus it is with mind, consciousness, and intuition – all operationally significant, all with indirectly measurable effects. Non-physical does not mean non-useful, non-real, or non-existent.”  – Tom Cambpell, physicist & consciousness explorer, author of "My Big TOE"

I will leave you with this famous quote by Nikola Tesla…

“The day science begins to study non-physical phenomena, it will make more progress in one decade than in all the previous centuries of its existence.”  Nikola Tesla

I can’t help but wonder what definition of non-physical Nikola Tesla had in mind… It does have its irony, doesn’t it?  I hope that what he meant is that he thought that scientists need to be a bit more open-minded to the study of non-directly-measureable phenomena that may not necessarily fall in the category of what they believe is real. That, in general, they should be more open minded to the study of those things which many would call imaginary or supernatural nonsense.

Perhaps we’ll always be stuck with our fuzzy definitions, because the ultimate reality may be truly ineffable and unbounded. But I do think that our curiosity, our imagination and thirst for knowledge will always end up beating our close-mindedness, our rigidity and unfounded beliefs. Thank goodness for that… !

References / further info:

What is Physicalism? http://plato.stanford.edu/entries/physicalism/#12

Hempel’s Dilemma: http://en.m.wikipedia.org/wiki/Hempel's_dilemma

Sean Carroll – Science of unobservable things: http://www.preposterousuniverse.com/blog/2008/03/15/science-and-unobservable-things/

Margaret Wertheim – The Limits of Physics: http://www.aeonmagazine.com/world-views/margaret-wertheim-the-limits-of-physics/