Understanding ‘TIME’ — Theories, Paradoxes and Possibilities
— Ever since man first noticed the regular movement of the Sun and the stars, he has wondered about the passage of time. Mankind started recording the movement of Moon and Sun since the last 30,000 years ago. And today, for us, nothing seems more basic or real than time, and every passing moment confirms the existence of time.
However, over the last few thousand years the philosophical debate on the nature of time has continued, and the truth is, that philosophers are not the only ones to have doubts about the true nature of time — physicists, too, ponder over the unreality of time.
Albert Einstein showed that time is an illusion; it is relative — it can vary for different observers depending on your speed through space — time slows down or speeds up depending on how fast you move relative to something else.
The Oxford dictionary defines Time as the indefinite continued progress of existence and events in the past, present and future regarded as a whole.
The definition does not elaborate upon the true nature of Time and I strongly feel that Time, as we know, is not an object or substance we can touch or see. And definitely, it is not just a dimension, quantity or a mere concept. Indeed, time consists of multiple aspects.
Intriguing!
So, I decided to take a journey into the complex world of Time to find out it’s real meaning and dwell upon the feasibility of ‘Time travel’!
As usual, I will start with the greatest minds and the original thinkers — the philosophers!
1. Indian Philosophy:
In ancient Indian Vedic philosophy, time is not seen as solely linear. Instead, it has both linear and cyclical elements. The universe goes through repeated cycles of creation, destruction, and rebirth, expounding to a cyclic view of time — a “wheel of time” or Kalachakra, in which there are repeating ages over the infinite life of the universe.
This concept was later followed by Buddhism, Jainism as well as the ancient Greeks and the Mayan civilizations.
2. Greek Philosophy
The early Greek philosophers generally believed that the universe and time was infinite with no beginning and no end.
In the 5th Century BCE, the Sophist philosophers asserted that time is not a reality, the reality is limited to what exists in the here and now, and the past and future are unreal and imaginary.
Zeno’s Paradoxes: Zeno’s paradoxes are a set of four paradoxes dealing with the aspects of continuous space and time. They support Plato’s doctrine that contrary to the evidence of one’s senses, the motion is nothing but an illusion.
Two famous paradoxes are :
Achilles and the Tortoise — — Achilles is unable to catch a plodding tortoise which has been given a head start, since during the time it takes Achilles to catch up to a given position, the tortoise has moved forward some distance.
This sequence also presents a second problem in that it contains no first distance to run, for any possible finite first distance could be divided in half, and hence would not be first after all. Hence, the trip cannot even begin :)
Interestingly, Aristotle saw time as an attribute of movement, as something that does not exist on its own but is relative to the motions of things. Aristotle argued that time is essentially a measurement of change, and therefore cannot exist without some succession or change. Thus, it requires the presence of a soul capable of “numbering” the movement! He also believed that, although space was finite, time was infinite, and that the universe has always existed and will always exist.
Aristotle also framed an interesting paradox about the existence of time: if time essentially consists of two different kinds of non-existence (the future — “not yet, and the past — “no longer”) separated by a nothing (the instantaneous and vanishing present or “now”), how then can we talk of time as actually existing at all?
3. Early modern philosophy — 17th and 18th Century
Realism and Antirealism:
On the one hand, Sir Isaac Newton postulated that time is part of the fundamental structure of the universe and that it can best be looked on as a dimension in which events occur in sequence. He asserted that ‘absolute time’ exists independently without being perceived. We and all the objects in the universe, are just temporarily “occupying” this Absolute Time! And we perceive only a fraction of — called ‘relative time’, which is a measurement of recognizable objects in motion like the Moon or Sun, from which we infer the passage of time.
But the anti-realist view, proposed by Newton’s great rival Gottfried Leibniz claimed that Time is just a convenient intellectual concept (like space and number) that enables us to sequence and compare events. Thus, time ceases to have any meaning unless there are objects with which it can interact or relate to.
Immanuel Kant described space and time as a part of the notions that are necessary to allow us to comprehend sensory inputs. He believed that Time is merely one element of the systematic framework we use to structure our experience.
Phenomenology
In the late 19th and early 20th Century, the German philosopher Edmund Husserl, in his famous book ‘Phenomenology of internal time consciousness’, asserted that we could not have any perception of the immediate present without some memory of the past and some expectation of the future to give it context.
The French phenomenologist Henri Bergson saw the fluid flow of time as composed of numerous tiny temporal particles, which are pieced together by our consciousness. He postulated that Time is entirely derived from subjective experience so that babies would not experience time directly but rather would have to learn how to experience it.
In his 1927 book Being and Time, the German phenomenologist Martin Heidegger concluded that we do not exist within time, but in a very real way we are time, and the whole concept of time is inseparable from the human experience.
Also, he noted that, because we can allow the past to exist in the present through memory, and even allow a potential future occurrence to exist in the present due to our intuitive abilities. So, we are not stuck in simple sequential or linear time but can step out of it almost at will.
4. Modern Philosophy — 20th century onward -
In the 20th Century, the philosophical debate on the nature of time continued unabated, given a new thrust by the work of the British philosopher J.M.E. McTaggart, in his paper — The Unreality of Time.
McTaggart argued that time is unreal because we see the present moment we are living through as the only ‘present time.’ But, all other moments, past and future, also either were or will be the present time at some point or other, which creates a contradiction. His analysis led to the ‘tensed and tenseless’ theories of the passage of time.
Presentism and Eternalism
The philosophy of time that takes the view that only the present is real is called presentism, while the view that all points in time are equally “real” is referred to as eternalism.
Thus, according to presentism, only present objects and present experiences can be said to exist truly, and things come into existence and then drop out of existence. So, there is no true past or future at all!
Eternalism, on the other hand, holds that such past events do exist, even if we cannot immediately experience them, and that future events that we have not yet experienced also exist in a very real way. The “flow of time” maybe just an illusion of consciousness, because, in reality, time is always present everywhere.
Endurantism and Perdurantism
Endurantism asserts the common sense view that, when an object continues to exist through time, it exists completely at different present time, which separates from the other previous and future instances.
Perdurantism, on the other hand, holds that something that continues to exist through time exists as a single continuous reality, and the thing as a whole is then the sum of all of its “temporal parts” or instances of existing.
This argument favors ancient Greece and famous Heraclitus’ statement.
The theory of Endurantism, tend to agree with Heraclitus, even though our common sense tells us that the river at one time and the river at another time are in fact the same river.
The latest Philosophical Ideas about time rely on the Modern Physics and it will be better to understand the Physics of time before discussing them.
To be continued…
