The achievements of Classical Greece in diverse
fields, especially literature (plays and history), mathematics, science,
philosophy, and the arts have profoundly influenced world culture. Especially
impressive is the direct narrative style of its writers, the realism and subtle
aesthetics of its arts.
But here I only wish to speak of physics, where,
unfortunately, Greece went wrong. The leading figure here is Aristotle (384–322
BCE), who was the first to use the word “physics” in the sense that it is
understood now. Motivated perhaps by biology, he conflated change in biological
and physical domains. He defined motion as the actuality of a potentiality,
which is fine in the “motion” of a living organism, but wrong otherwise. Motion
defined this way requires the assumption of an absolute frame and other
imaginary schema. He gave example of four types of change, namely change in
substance, in quality, in quantity and in place, without providing logical
bases for this assertion.
Aristotle was extremely influential for nearly 2,000
years in the Western and the Islamic worlds as he was embraced by the orthodoxy
in both Christianity and Islam. Since physics is fundamental to cosmology, his
thoughts had a profound impact on the history of Western science.
According to Aristotle, the sun, the moon, planets
and stars are embedded in perfectly concentric crystal spheres that
rotate at fixed rates. The celestial spheres are made up of the element ether
which supports uniform circular motion.
He took the terrestrial objects to be composed of
four other elements that rise or fall. The earth, the heaviest element, and
water, fall toward the center of the universe; hence the earth and the oceans
constitute our planet. At the opposite end, the lightest elements, air and
fire, rise up and away from the center.
With the rise of Christianity, Europe
was cut off from its pagan past and many Greek originals were lost or preserved
only in translations. Aristotle’s Physica and De
Caelo (On the Heavens) were translated from Arabic
to Latin in the twelfth century. Soon after, Thomas Aquinas in his Summa
Theologica (1265–1274) reconciled Aristotle’s ideas to the demands of
Christian dogma.
This explains why the challenge to the idea of the
earth being the center of the solar system (or the universe) was such a big
thing in Europe. In 1600, Giordano Bruno was burnt at the stake for his heresy
against the geocentric model. Galileo was tried by the Inquisition, found vehemently
suspect of heresy, and forced to recant. He spent the rest of his life
under house arrest, before dying in 1642.
In spite of the fog that Aristotle’s ideas generated
there were individuals who did amazing physics. In particular, let me mention
Archimedes (287–212 BCE) who made brilliant contributions to geometry and
impressive application of mathematics to physical phenomena such as
hydrostatics and statics. But of course his physics did not cover problems of
motion, where Aristotle held sway.
Kaṇāda’s
physics
This brings me to Kaṇāda,
son of Ulūka, who I am going to argue is the greatest physicist of
antiquity. He anticipated the laws of motion, and he attempted something that
no other physicist has dared to do: he created a formal system that includes
space, time, matter, as well as observers.
Kaṇāda (कणाद), the author of
the Vaiśeṣika Sūtra, is generally believed to have lived around 600 BCE. He is credited with the idea of the atom as a
passing footnote in history books. For example, in A.L. Basham’s
well-regarded The Wonder that Was India, he gets cursory reference
in one line.
The Vaiśeṣika Sūtra has been studied by philosophers
but not physicists. I tried to remedy that a couple of years ago in the
volume Matter and Mind: The Vaiśeṣika Sūtra of Kaṇāda. In
this book of science, perhaps Kaṇāda’s most impressive assertion is that all
that is knowable is based on motion, which gives centrality to physics in
the understanding of the universe.
For context, note that Newton’s three
laws of motion are: 1. An object remains in the state of rest or motion
unless acted upon by force; 2. Force equals mass times acceleration; 3. To
every action there is an equal and opposite reaction. But Newton considered
space and time to be absolute without explaining what that meant. Kaṇāda’s propositions below are powerful because he makes
few assumptions.
Propositions
and laws
To give the reader a flavor of the astonishing
brilliance of Kaṇāda’s vision, I will pick just a few of his propositions to
illustrate his system and then I will provide the sutras that describe physical
law related to motion. Note that his atoms are in perpetual motion and so he
distinguishes between internal and outer motions of an object.
Proposition 1. कर्मं कर्मसाध्यं न विद्यते॥१।१।११॥
[Internal] motion does not lead to [outer] motion.
Proposition 2. कारणाभावात्कार्याभावः ॥१।२।१॥
In the absence of cause there is an absence of
effect.
Proposition 3. सामान्यं विशेष इति बुद्ध्यपेक्षम् ॥१।२।३॥
The properties of universal and particular are associated
with the mind.
Proposition 4. सदिति यतोद्रव्यगुणकर्मसु सा सत्ता ॥१।२।७॥
Substance, attribute, and motion appear out of
potential (sattā).
Proposition 5. सदकारणवन्नित्यम् ॥४।१।१॥
What is without cause is eternal (nitya).
The propositions present general principles that are
most reasonable. For example, the idea of symmetry is included in the principle
of nitya. Now I present what may be called Kaṇāda’s Laws of Motion.
Law 1. संयोगाभावे गुरुत्वात् पतनम् ॥५।१।७॥
In the absence of action, the object falls by
gravity.
Law 2a. नोदनविशेषाभावान्नोर्ध्वं न तिर्य्यग्गमनम् ॥५।१।८॥
In the absence of a force, there is no upward
motion, sideward motion or motion in general.
Law 2b. नोदनादाद्यमिषोः कर्म तत्कर्मकारिताच्च संस्कारादुत्तरं तथोत्तरमुत्तरञच् ॥५।१।१७॥
The initial motion of an arrow is caused by a force,
from that motion is potential (saṃskāra) from which is the motion that
follows and the next and so on similarly.
Law 3. कार्य्यविरोधि कर्म ॥१।१।१४॥
Action is opposed by reaction.
This list above is just my personal arrangement of
propositions and laws. The first law is effectively
equivalent to Newton’s first law. The second law, in two parts, falls a
bit short, although it has something much more about potential. What is missing
is an explicit definition of mass but we cannot be sure if that was not an
element of the exposition. Kaṇāda’s third law is
identical to Newton’s third law.
On the Vaiśeṣika
Sūtra
The Vaiśeṣika Sūtra is just over 370 sutras in 10
chapters, where each chapter has two sections. Calling physical law dharma, the
first chapter defines and discusses three categories of substance, attribute,
and action. The second chapter describes the nine substances. The third chapter
deals with the self and the mind.
The first part of the fourth chapter speaks of the eternality of atoms and how sensory
perception leads to knowledge. The second part of the fourth chapter deals with
the composition of bodies. The fifth chapter deals with action, and the sixth
chapter deals with the discipline that facilitates acquisition of knowledge.
The seventh chapter elaborates on atomicity and
further discusses the nature of ether, mind, space and time. The eighth and
ninth chapters describe various types of cognition and negation. The tenth chapter
discusses cause. As this summary indicates, the text is a systematic exposition
of principles and laws to describe physical reality.
The Vaiśeṣika categories are for space-time-matter
and for attributes related to perception by sentient agents. Kaṇāda starts with
six categories (padārthas) that are nameable and knowable, proposing
they are sufficient to describe everything in the universe from concrete matter
to the abstract atom.
The six categories are: dravya (substance), guṇa
(quality), karma (motion), sāmānya (universal), viśeṣa (particularity), and
samavāya (inherence). The first three of these have objective existence and the
last three are a product of intellectual discrimination. Universals (sāmānya)
are recurrent generic properties in substances, qualities, and motions.
In it the gross visible matter is constructed out of
the varying motions of aṇu, its most fundamental particle. The mind
is not an empty slate; the very constitution of the mind provides some
knowledge of the nature of the world. The four proofs through which correct
knowledge is acquired are direct perception, inference, analogy, and verbal
testimony. In other words, the system represents a logical and scientific
approach to reality.
Particularities (viśeṣa) reside exclusively in the
eternal, non-composite substances, that is, in the individual atoms and minds,
and in the unitary substances ether, space, and time. Inherence (sāmānya) is
the relationship between entities that exist at the same time.
Of the six categories, the basic one is that of
substance and the other five categories are the ones that the mind associates
with the substance. Thus observers belong to the system in an integral fashion.
If there were no sentient beings in the universe then there would be no need for
these categories.
Atomic
transformations
There are nine classes of substances, some of which
are non-atomic, some atomic, and others all-pervasive. The non-atomic ground is
provided by the three substances of ether (ākāśa), space (dik), and time (kāla),
which are unitary and indestructible; a further four, earth (pṛthvī), water
(āpas), fire (tejas), and air (vāyu) are atomic composed of indivisible, and
indestructible atoms (aṇu); self or consciousness (ātman), which is the eighth,
is omnipresent and eternal; and, lastly, the ninth, is the mind (manas), which
has atomic dimensions.
Let the basic atoms of pṛthivī, āpas, tejas, and
vāyu be represented by P, Ap, T, and V, respectively. The eternality of the
atoms is true only under normal conditions, and during creation and
destruction, the atoms arise in a sequence starting with ākāśa and
absorbed in the reverse sequence in the end of the world. The sequence
of evolution of the elements is given as V→T→Ap→P. The V and T atoms are
without mass, whereas P and Ap atoms have mass.
It is significant that consciousness is listed
before mind, suggesting that it is the medium through which mind’s
apprehensions are received. The atoms of earth, water, fire and air are
different and this difference arises out of the different ways the fundamental
atom of materiality combines with itself in different arrangements. In other
words, Kaṇāda foresaw the emergence of chemistry from physics.
Kaṇāda’s ideas have always been central to Indian
physical thought and they influenced the emergence of modern science indirectly.
This article was first published here.
eSamskriti.com has received permission from the author to publish it on the
site.
Shri Subhash Kak is an Author and Scientist
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