FREE online courses on Concepts of Ayurveda - Peelupaka or Chemical Change
Peelu means paramanu or atoms, and paka
means the transformation or change brought about in their relationship under the
influence of heat and light. It is in this context that the reference made above
and elsewhere to the fact that (i) the paramanus ( atoms and molecules ) do not
occur in nature in an uncombined state, and (ii) they combine in twos, three,
four, and so. on, to form molecules of Dwayanukas, Thrayanukas, Chaturanukas
etc., becomes significant. The Vaiseshikas note that paramanus always combine,
separate and recombine under the influence of heat and light or Tejas, which is
of two kinds viz., endothermic and exothermic. The observed difference between
one substance and another, or in fact, between all substances in regard to their
colour, consistency, roughness, smoothness, etc., is held to be due to what is
know as Pakabheda or difference in chemical reactions. " It is heat and heat
alone that can cause transformation in respect of colour, taste, smell or
physical characteristics of paramanus. These depend on (a) the nature of the
constituent substances in contact; (b) the intensity or degree of heat described
in terms of Khara, Mrudu and Madhyapakas and, (c) the species of the Tejas
corpuscles that impinge on paramanus or atoms ( and molecules ) and the nature
of the impact."
Stated in brief, the Vaiseshika school hold
that " there is decomposition into homogeneous atoms (paramanus) transformation
of atomic qualities ( qualities of paramanus) and finally their recombination,
all under influence of heat and light."
The views expressed above are illustrated
with the following example:
In the process of the baking of a raw clay
pot by a otter, quick succession of changes are observed to take place in the
material of the pot, in respect of its colour, density, consistency etc.,
similar to changes that take place during the process of the cooking of food.
The Vaiseshikas interpret and explain the successive phases of transformation
and change, as due to the decomposition of the pot in to their component atoms
(paramanus) and their subsequent recombination under altered spatial
relationship, different from their original disposition in the material of the
raw clay pot before the same was subjected to the action of heat. The entire
process of change in the molecular and atomic steps viz.,
i.
the decomposition of the material of
the pot into its molecules, in the first stage;
ii.
the decomposition of the molecules into
their constituent paramanus, in the second stage;
iii.
the recombination of the paramanus in
new relationship and altered spatial alignments into molecules of two
paramanus - Dwaya - nukas: into molecules of
three
paramanus - Thrayanukas, and into molecules
of four
paramanus - Chaturnukas, and forth.
Thus, in the finished baked pot, the spatial
relationship the originally existed between one paramanu and another in the
material of the original unbaked clay pot is altered, and altogether new
relationships are established resulting in the exhibition of new properties in
respect of colour, density, consistency etc, of the baked pot.
The process of transformation and changes
referred to above, in terms of Kala or
Time, are stated to take place as follows:
It takes nine moments or Kshanas for
completion of the consummation of the change from the unbaked to baked state in
the clay pot. In the first moment (Kshana), the Dvayanuka is destroyed. In the
second moment (Kshana) the original black colour of the unbaked clay is
destroyed. In the third moment (Kshana) a different colour - red - is generated
due to the influence of heat and light. IN the fourth moment (Kshana) the
paramanus combine to form the new substance. In the fifth moment (Kshana), the
paramanus separate themselves from their old status (i.e) from their former
place or the previous position. In the sixth moment (Kshana) they separate
themselves again. In the seventh movement (Kshana) they combine with other
paramanus. In the eighth moment (Kshana) they again align themselves as
molecules of two paramanus (i.e) Dwayanukas. In the ninth moment (Kshana), the
specific or the characteristic properties of the paramanus, such as colour, etc,
manifest in the constituents of the material of the now fully baked pot. Thus,
in nine moments (Kshanas), the soft, dark, unbaked clay pot is transformed into
the hard and red baked pot.
It will be seen from the forgoing that the
Vaiseshikas held that a raw clay jar or pot is baked, the old jar or pot as the
case may be is destroyed, involving pari pasu the decomposition of the several
compounds of its Dwayanukas. The production of new red colour in the molecules
themselves is stated to be brought about by thermal influence on the compounds
formed by them eventually producing a new jar or pot, as the case may be. The
rapidity with which the successive steps in the process of transformation has
been envisaged to occur is stated to prevent the eye from detecting each
consecutive individual step. The following of purely the Nyaya school assert
that, "the Tejas penetrates into the different compounds of two or more atoms
(Paramanus) and thereby changes, not the jar, but its colour etc. The jar is
still the same jar; only it is red and not black,"
The conception of physical and chemical
changes of Vaiseshikas viz., the old theory of Peelupaka are suggestive of the
following important facts of physical chemistry:
(1) The paramanus, which as noted earlier
correspond to matter described upto a few micrograms, and which for purposes of
following and interpreting chemical reactions was found to be sufficient enough
as now evidenced, are in a constant state of vibratory motion.
(2) The Vaiseshikas have resolved all
physical action into motion - molar, molecular and subtle - of mass, molecules
and atoms respectively. This motion is stated to be of the whirling or rotatory
and circular, and also harmonic (e.g. vibration) in kind. This motion, as noted
earlier, is spoken of as 'parispanda.' All matter - atoms, molecules and
aggregates of molecules - are always in a state of parispanda.
(3) The fact that paramanus do not in
nature occur in an uncombined state having been posited, the problem of what is
known to-day as pseudo - unimolecular reaction does not arise and such a
reaction is usually a rare phenomenon. The more common and frequent reaction as
contemplated by the theory of two, three and four molecules, should remind us of
bimolecular termolecular and still higher reactions of modern physical
chemistry.
(4) Physico - chemical changes and
transformations involve contact between and collision of atoms and molecules
respectively, a fact which is implied in Peelupaka.
(5) Apart from the fact that associations
and dissociations of paramanus or molecules in the consecutive steps of
Peelupaka imply the utilisation and release of energy respectively, the fact
that thermal influences take a leading part in accelerating or retarding the
process of paka or reactions will also emerge. The theory of Peelupaka implies
the formation of Exothermic compounds and Endothermic compounds.
(6) Stated in terms of Kala or Time, the
successive steps of changes and transformations envisaged in Peelupaka instanced
with the example of the baking of the clay pot, is stated to occupy one Kshana
or 2/45 of a second for each step.