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What Is Consciousness?

How to define the elusive concept of consciousness.

Key points

  • Consciousness is the active and subjective experiencing aspect of an experience.
  • Consciousness is what transforms a biochemical state into an experience.
  • Although we have mapped brain activity to specific conscious perceptions, we still don't know how this gives rise to conscious experiences.

Consciousness is what we are most familiar with. Feeling the sun's warmth on our face, the joy of seeing someone we love, or the thrill of being on a rollercoaster—every single experience we ever had, from sensations to thoughts and emotions, is linked to consciousness. It seems paradoxical, but despite being at the centre of every experience, consciousness is difficult to define and still poorly understood scientifically.

We know more about distant galaxies and the deepest ocean regions than we do about our consciousness. Even though consciousness has been discussed by philosophers for millennia and has become an active and thriving field of scientific research, it remains largely a mystery–but a strange mystery, one that we may not understand well but are intimately acquainted with.

So, what exactly is consciousness? Many have tried to answer this seemingly simple question (I will cover most of the influential views on this blog), but a universally agreed-upon definition still seems elusive. Let’s start our exploration with a trip to the dentist.

Experiencing an Experience

Local anesthesia can make dental surgery a lot more bearable. Specialised neurons that detect pain called nociceptors still respond even when under local anesthesia and try to send out signals to alert the brain to tissue damage inside the mouth. While some local anesthetics reduce nociceptor activity, many function by blocking these signals from being passed on so that the message never reaches the brain (another example of this is spinal epidural anesthesia, where the signaling pathway is blocked in the spinal cord rather than at the source nociceptors; Olschewski et al., 1998). The tissue damage in the mouth is simply a biological state, and any nociceptor response is just a biochemical reaction, an event, or an occurrence without any associated experience.

When we bite into a juicy apple (after recovering from our dental surgery), our minds cannot directly interact with the apple. Whatever the mind may be, it cannot directly taste the sweetness, sense the crunchy texture, or smell the chemicals released into the air. We need the complex sensory machinery inside our bodies to pick up on these things, encode them into neural signals, and send them to the brain. When the upward signaling is interrupted (like it was by the local anesthesia at the dentist), all of this is merely a physiological state or a unique biochemical configuration of our bodies.

However, if these signals reach our brains when awake and focused, something extraordinary happens: The biological signals trigger a subjective conscious experience. We still don’t know much about how or why this happens, but consciousness lives on as an indisputable aspect of our minds. Although mysterious, it is also one of the most beautiful and meaningful aspects of our human experience: It makes life worth living and gives us an innate sense of value and worth. There are no laws against throwing a rock but very strict laws against throwing rocks at a human being.

The simple reason is that unlike rocks—as far as we know—human beings have the capacity to experience both pain and joy. All human rights and the famous unalienable right to life, liberty, and the pursuit of happiness, found in the U.S. Declaration of Independence, are based on the human capacity to have experiences. Consciousness is the basis for our experiences and undergirds all of this.

In its most basic sense, consciousness is linked to experience. In a way, it turns a state of the world or a specific configuration of atoms, molecules, organs, and everything else into an experience. Another way to look at it is as the active experiencing of an experience.

Source: Alexandru Zdrobău | Unsplash
Behind our outer façade lies a rich inner world based on conscious experiences.
Source: Alexandru Zdrobău | Unsplash

Towards Neural Correlate and Back to Experience

Several decades of thriving research have uncovered much of what lies behind our conscious experiences, such as the complex and intricate brain processes required to piece together what we sense coherently. Even decoding a sound's origin in three-dimensional space requires complex computation within a specialised neural architecture. Yet, we are not directly aware of any of these myriad operations that are going on behind the scenes and effortlessly turn toward the direction of a loud sound. These fascinating insights can describe the brain activity associated with specific conscious perception forms in great detail. We already have a rich catalogue of such neural correlates, and new findings are frequently added.

The problem is that while neural correlates highlight the brain’s necessary work in the background that makes specific conscious experiences possible, they fail to explain such experiences themselves. The processes are unconscious, and even the results can often be unconscious, like when we are distracted or when a stronger stimulus overrides another. In those cases, the exact same processes do not result in a conscious experience.

A rollercoaster can provide a thrilling ride, but if it runs empty with no one riding it, no thrill is experienced. This does not mean that there is a little person inside watching the “theatre of the mind”—what the British philosopher Gilbert Ryle (1949/2002) mockingly called “the dogma of the Ghost in the Machine.” A majority of scientists and philosophers reject this notion. However, it does mean that even though neural correlates of consciousness are incredibly useful, they don’t fully explain what consciousness is.

Anil Seth, one of the leading researchers in this field, suggests that the ultimate (or what he calls the “real question of consciousness”) is answering why a particular brain activity results in a specific conscious experience and not merely establishing that it does (Seth, 2021).

Experiences need explaining beyond their mechanistic underpinnings. Some philosophers have gone as far as to suggest that what is experienced is an illusion (Frankish, 2016). Yet, even in this extreme scenario, if the content of an experience is truly illusionary (which few accept), the experience itself would still be real. Any philosophical, psychological, or neurobiological theory of consciousness is incomplete without a full account of experiences, which brings us back to the act of experiencing.

What exactly is consciousness?

So, what exactly is consciousness? It is what we are most familiar with and what undergirds every perception, emotion, and thought we have. At the same time, it is an elusive notion that is difficult to define. I would suggest that it is linked to experiences: It is the subjective and active aspect, the experiencing of an experience.


Frankish, K. (2016). Illusionism as a theory of consciousness. Journal of Consciousness Studies, 23(11-12), 11-39.

Olschewski, A., Hempelmann, G., Vogel, W., & Safronov, B. V. (1998). Blockade of Na+ and K+ currents by local anesthetics in the dorsal horn neurons of the spinal cord. The Journal of the American Society of Anesthesiologists, 88(1), 172-179.

Ryle, G. (2202). Descartes’ myth (original work published in 1949). In D. J. Chalmers (Ed.) Philosophy of mind: Classical and contemporary readings. Oxford University Press.

Seth, A. (2021). The real problem of consciousness. Psychology Today. URL:

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