Time, Consciousness, Philosophers' Zombies, Materialism and Dualism
Imagine a universe that is empty except for a ticking clock. Does time exist there?
The answer could be YES, the clock will keep ticking till it runs down.
Does time then stop? What happens between ticks?
Or it could be NO because there is no such thing as sound; because there is no air, no light, and no conscious observer to hear the tick or see the face of the clock.
Or it could be NO because time is an illusion, as originally stated in 1907, an idea later taken up by various physicists in the form of a timeless universe.
Physical And Mental Time
Physical Time is time in Physics, a variable in the mathematical formulae we use to describe our world. An analogue of Physical Time can be observed in any world that contains matter which obeys regular behaviours that can be described as laws and modeled by mathematics.
Clock Time, the time measured by a physical clock, is a special case of Physical Time. Does a clock tick if there is nobody to hear it? A sound requires a conscious being with ears to hear it and a sight requires a conscious being with eyes to see it. In the clock world the clock would keep going but, with no one to hear or see it, Mental Time would not exist by definition and Clock time, which needs a conscious observer, would not exist either.
Mental Time is the time we experience as conscious beings. Dreams may take only a few seconds to an external observer but last a long time to the dreamer, while a long time in the outside world may go by in a flash, as anyone who walked for ten minutes but cannot recall those minutes knows. Mental Time would not exist without Consciousness and Timeless Consciousness, consciousness without Mental time is hard to imagine, though mystics often say that when they experience a mystical insight they experience the universe without experience of time.
A Philosopher's zombie is something that acts as if it is conscious but is not. A zombie world is a logically consistent world in which conscious does not exist.
Time, Consciousness, Materialism And Dualism
Chalmers used a conceivability argument to conclude that Materialism fails if and only if zombies are conceivable then discusses Panpsychism, which he takes as the notion that microphysical objects possess consciousness and Panprotopsychism, the idea, also proposed by physicist Max Bohm, that microphysical objects possess protoconscious properties. All these positions have problems.
Materialism must explain how consciousness arises from unconscious matter, or prove consciousness is an illusion (and how an illusion can be experienced in the absence of consciousness). Dualism must explain how a non material consciousness can influence matter. Panpsychism and Panprotopsychism suffer from the combination problem, the problem of how consciousness, for example ours, can arise from the (proto)conscious properties of the microphysical objects which we are comprised.
If Materialism fails because a possible world contains a philosopher’s zombie Mental and Physical Time could have a different metaphysical and ontological status with some consciousness not grounded in Physics implying Mental Time exists independently of Physical Time.
If Dualism fails physical and mental time are entangles, Consciousness is grounded in Physics, though not necessarily in neurobiology or confined to the brain and mental time is ultimately grounded in Physics, though not constrained by it (we can imagine things not allowed by Physics)
For Dualism to fail zombies and zombie universes must be inconceivable. In this case Physical time could not therefore continue if all consciousness vanished since that would imply a zombie universe which contradicts the assumption a zombie universe is inconceivable. Physical Time then depends on Consciousness for its existence, and thus on Mental Time. Since Materialism requires all events to have a physical cause Mental Time would ultimately depend on Physical Time.
For Materialism to fail zombies and zombie worlds must be conceivable. In this case a world that contains only consciousness is also conceivable. In such a world Physical Time would clearly not exist though Mental Time could exist. This means that resolving the question of whether time exists in the clock world requires resolution of the Materialism-Dualism question.
One of our normal intuitions about time is that it is a line of durationless instants where we can assign a number to each point. The present moment, NOW is a special time the past being fixed and inaccessible with the future uncreated and malleable. Everything about this intuition is debatable.
Another model is that Time is like an hourglass with grains of time passing from the future through the needle’s eye of now into the jumbled heap of the past. Again everything about this model is debatable.
Smolin  espouses Temporal Naturalism, whichadopts this common intuition, but he says nothing about whether time is continuous. Temporal Naturalism is compatible with several formulations of dynamics and isConsciousness friendly, or at least can accommodate Qualia, which can be thought of as the fundamental and indivisible components of Consciousness, such as “seeing red” or “hearing b#”but does not take consciousness as fundamental and thereby makes zombies and a zombie universe conceivable which, following Chalmers, means Materialism failsand implies dualism is correct.
The assumption that the past no longer exists and the future does not yet exist appears to contradict experimental results from Wheeler’s delayed choice two slit experiment which shows that our present can affect our past, or more generally that the future can affect the past and seems incompatible with Temporal Naturalism.
A Timeless Universe?
Barbour  claims Physical Time is redundant in Classical Physics, that Time is created by what the universe does and that we abstract time from motion, but does not explain what motion in a timeless universe actually means. At a very high and perhaps oversimplified level this argument is that in Classical Physics the world is described mathematically as a set of points in a high dimensional space and a particle traces out a path in this space with time merely being a measure of the distance between two points. He shows how time can be eliminated in such a system and notes that. the path a particle takes between two points, in the time based description, minimises a physical quantity called the Action and that this specifies the position of the particle. After noting that this principle can also be formulated for General Relativity and Quantum Systems Barbour concedes that it may be impossible to banish time entirely form Physics since “the universe may be infinite and black holes pose problems”.
It is hard to see how consciousness and a sense of time could arise in such a universe unless we accept dualism and envisage individual consciousnesses as focussing on successive points of the block universe crawling across and focusing on various points of the block universe, which entails Mental Time being different from Physical Time (which by hypothesis, does not exist in a static universe).
Suppose time is an illusion and the universe is timeless. Consciousness, if it includes a sense of time, will then be an illusion and we are zombies deceived into thinking we are not zombies, which makes a zombie universe conceivable and allows for the possibility that consciousness can be external to the timeless universe. In that case it is hard to see how consciousness could interact with the timeless universe. Recent proposals that quantum behaviour can be explained by interaction with multiple parallel classical universes suggest how such an interaction could happen and if all these universes are also materialist then they should also include quantum theory and consciousness
General considerations only say that if Materialism is true then the world must include consciousness. In that case Mental and Physical time are entangled. Temporal Naturalism matches our normal intuitions of time but as it does not take consciousness as fundamental leaves the dualist-materialist question open but tilts the scales in favour of dualism. A timeless universe makes a dualist position hard to avoid and it seems proponents of a timeless world and illusory time are conflating Physical and Mental Time
If Materialism is true then the question of how mental time can arise from physics can be called the hard problem of Time by analogy with Chalmers’ hard problem of Consciousness and arises whether or not time is real. Neither temporal naturalism or a timeless universe resolves this question.
Simply saying that Time and/or consciousness are illusions does not resolve the problem for they would be very persistent illusions and even if illusions, the illusions themselves are real and something or someone must be experiencing them.
About The Author
This is a condensed version of a chapter in my forthcoming book about Time.
Trained as a mathematician and Physicist I spent 15 years as an IT contractor in various countries but that will be the subject of another book