[Footnote ref 369]
The other tendency, namely that of tamas, has to be helped by the liberated rajas of aha@mkara, in order to make itself preponderant, and this state in which the tamas succeeds in overcoming the sattva side which was so preponderant in the buddhi, is called _bhutadi._ From this bhutadi with the help of rajas are generated the _tanmatras,_ the immediately preceding causes of the gross elements. The bhutadi thus represents only the intermediate stage through which the differentiations and regroupings of tamas reals in the mahat proceed for the generation of the tanmatras. There has been some controversy between Sa@mkhya and Yoga as to whether the tanmatras are generated from the mahat or from aha@mkara. The situation becomes intelligible if we remember that evolution here does not mean coming out or emanation, but increasing differentiation in integration within the evolving whole. Thus the regroupings of tamas reals marks the differentiation which takes place within the mahat but through its stage as bhutadi. Bhutadi is absolutely homogeneous and inert, devoid of all physical and chemical characters except quantum or mass. The second stadium tanmatra represents subtle matter, vibratory, impingent, radiant, instinct with potential energy. These "potentials" arise from the unequal aggregation of the original mass-units in different proportions and collocations with an unequal distribution of the original energy (_rajas_). The tanmatras possess something more than quantum of mass and energy; they possess physical characters, some of them penetrability, others powers of impact or pressure, others radiant heat, others again capability of viscous and cohesive attraction [Footnote ref 370].
In intimate relation with those physical characters they also possess the potentials of the energies represented by sound, touch, colour, taste, and smell; but, being subtle matter, they are devoidof the peculiar forms which these "potentials" assume in particles of gross matter like the atoms and their aggregates. In other words, the potentials lodged in subtle matter must undergo peculiar transformations by new groupings or collocations before they can act as sensory stimuli as gross matter, though in the minutest particles thereof the sensory stimuli may be infra-sensible (_atindriya_ but not _anudbhuta_) [Footnote ref 371].
Of the tanmatras the _s'abda_ or _akas'a tanmatra_ (the sound-potential) is first generated directly from the bhutadi. Next comes the _spars'a_ or the _vayu tanmatra_ (touch-potential) which is generated by the union of a unit of tamas from bhutadi with the akas'a tanmatra. The _rupa tanmatra_ (colour-potential) is generated similarly by the accretion of a unit of tamas from bhutadi; the _rasa tanmatra_ (taste-potential) or the _ap tunmatra_ is also similarly formed. This ap tanmatra again by its union with a unit of tamas from bhutadi produces the _gandha tanmatra_ (smell-potential) or the _k@siti tanmatra_ [Footnote ref 372]. The difference of tanmatras or infra-atomic units and atoms (_parama@nu_) is this, that the tanmatras have only the potential power of affecting our senses, which must be grouped and regrouped in a particular form to constitute a new existence as atoms before they can have the power of affecting our senses. It is important in this connection to point out that the classification of all gross objects as k@siti, ap, tejas, marut and vyoman is not based upon a chemical analysis, but from the points of view of the five senses through which knowledge of them could be brought home to us. Each of our senses can only apprehend a particular quality and thus five different ultimate substances are said to exist corresponding to the five qualities which may be grasped by the five senses. In accordance with the existence of these five elements, the existence of the five potential states or tanmatras was also conceived to exist as the ground of the five gross forms.
The five classes of atoms are generated from the tanmatras as follows: the sound-potential, with accretion of rudiment matter from bhutadi generates the akasa-atom. The touch-potentials combine with the vibratory particles (sound-potential) to generate thevayu-atom. The light-and-heat potentials combine with touch-potentials and sound-potentials to produce the tejas-atom. The taste-potentials combine with light-and-heat potentials, touch-potentials and sound-potentials to generate the ap-atom and the smell-potentials combine with the preceding potentials to generate the earth-atom. The akas'a-atom possesses penetrability, the vayu-atom impact or mechanical pressure, the tejas-atom radiant heat and light, the ap-atom viscous attraction and the earth-atom cohesive attraction. The akasa we have seen forms the transition link from the bhutadi to the tanmatra and from the tanmatra to the atomic production; it therefore deserves a special notice at this stage. Sa@mkhya distinguishes between a kara@na-akas'a and karyakas'a. The kara@na-akas'a (non-atomic and all-pervasive) is the formless tamas--the mass in prak@rti or bhutadi; it is indeed all-pervasive, and is not a mere negation, a mere unoccupiedness (_avara@nabhava_) or vacuum [Footnote ref 373]. When energy is first associated with this tamas element it gives rise to the sound-potential; the atomic akas'a is the result of the integration of the original mass-units from bhutadi with this sound-potential (_s'abda tanmatra_). Such an akas'a-atom is called the karyakas'a; it is formed everywhere and held up in the original kara@na akas'a as the medium for the development of vayu atoms. Being atomic it occupies limited space.
The aha@mkara and the five tanmatras are technically called _avis'e@sa_ or indeterminate, for further determinations or differentiations of them for the formation of newer categories of existence are possible. The eleven senses and the five atoms are called _vis'e@sa,_ i.e. determinate, for they cannot further be so determined as to form a new category of existence. It is thus that the course of evolution which started in the prak@rti reaches its furthest limit in the production of the senses on the one side and the atoms on the other. Changes no doubt take place in bodies having atomic constitution, but these changes are changes of quality due to spatial changes in the position of the atoms or to the introduction of new atoms and their re-arrangement. But these are not such that a newer category of existence could be formed by them which was substantially different from the combined atoms.
The changes that take place in the atomic constitution of things certainly deserve to be noticed. But before we go on to this, it will be better to enquire about the principle of causation according to which the Sa@mkhya-Yoga evolution should be comprehended or interpreted.