Jain philosophy holds matter to be a corporeal substance.[1] Rūpī means that which possesses colour, smell, taste and touch.[2] Out of five astikāyas only pudgala is corporeal. There are many kinds of transformations in matter. In Bhagavatī, there is a mention of five kinds of transformations in matter i.e. transformation in colour, smell, taste, touch and configuration.[3] Sthānāṅga illustrates four kinds of transformations.[4] There we do not find the illustration of configuration. This expresses the fact that the defining characteristics of matter are colour, smell, taste and touch. All the four are possessed by both the atom as well as by the aggregate. Although configuration exists in matter but transformation in forms or structure occurs in skandha (aggregate) only. It cannot happen in atoms. Hence, this quality in configuration is not the defining characteristic of matter as a whole. That is the reason why the ācāryas of the post-canonical age formulated the two defining aphorisms of matter such as 'sparśa-rasa-gandha-varṇavantaḥ pudgalāḥ'[5] and śabda-bandha-saukaṣmya-sthaulya-sansthāna-bheda tamaśchāyāta-podyotavantaḥ.[6] This means śabda (sound) etc. are the attributes of matter but these do not exist in atoms. They exist only in the aggregate form of matter.[7] Atom and aggregate do not have similar number of touch etc. An adequate analysis of this is available in Bhagavatī.
Each atom possesses one colour, one smell, one taste and two touches.[8] Atom possesses one kind of colour out of five, one kind of smell out of two, one kind of taste out of five and two kinds of touch out of the eight. As to which two types of touch will exist and what will be the combination, four options are provided in this regard and they are as follows-
1. Cold and viscous or 2. Cold and dry or
3. Hot and viscous or 4. Hot and dry.[9]
The aggregates having different number of units (pradeśa) have different options of colour, smell etc. which can be understood by the following table:[10][*]
There can be many alternatives between the colour-colour, taste-taste and touch-touch among aggregates of two pradeśas and more than that. Bhagavatī has detailed information about it.[11] A seeker must survey that part of Bhagavatī.
An aggregate of two units to a subtler aggregate of infinite units has either of two, three or four touches out of cold, hot, viscous and dry touches.[12] Thus, these aggregates are agurulaghu i.e. masslesss. The gross aggregate of infinite units possesses four to eight touches. When this aggregate possess four kinds of touch, then the combination can be of any four out of eight kinds of touches. The only condition is that light and heavy, these two kinds of touch do not exist simultaneously. In the condition, where five or more than five touches are possessed then even light and heavy can co-exist together.[13] So these aggregates are supposed to have mass irrespective of whether they are composed of four touches, five, six, seven or eight touches. Heavy and light, these two kinds of touches are the regulator of mass. Hence, there is a possibility of mass in the gross aggregate of infinite units having even four kinds of touches.