According to the Vedic account of creation in the Upanishads, the Mahabhutas or great elements proceed from most subtle to most gross: Akasha -> Vayu -> Agni -> Apah -> Prithvi. Meaning, Space -> Air/wind -> Fire/light -> Water -> Earth. At the same time, each corresponding element is created with a Tanmatra, or subtle element. These subtle elements are the elements of perception, hearing, touch, sight, taste, and smell.
Each sensory element is associated with it's particular gross element as well as those more subtle than it, as shown in this picture.
- Space -> sound
- Air -> sound and touch
- Fire or light -> sound, touch, and sight
- Water -> sound, touch sight, and taste
- Earth -> sound, touch, sight, taste, and smell
Now, my question is, what is the relationship between the subtle sense element and it's associated gross element. Particularly, how is sound a property of Akasha?
In my understanding, space or Akasha is defined as the all-pervading substrate that contains the other elements. So if you remove the other four elements, you're left with just Akasha. Likewise, the four elements cannot exist without Akasha as their substrate. But then how is it associated with sound, since sound requires air (Vayu) to travel and cannot travel alone in space (Akasha)? Sound requires some reverberating medium to propagate through. If sound can truly travel without the aid of the other four elements, then it's probably due to some dark matter or something unknown.
Or possibly this Akasha and Shabda are referring to not our gross plane, but a subtle one, where subtle element Shabda can travel through subtle element Akasha.
Anyways, when I googled this, I came across this article by a Mechanical Engineer at Steven's Institute of Technology, NJ, who says that according to the Vedas, the relationship between sound and space is that only sound is affected by space and not any other sense perception. In other words, space qualifies sound only, and no other sense perception. If you are in a closed room, and the temperature is the same, walls are made of same material, air density is the same, and lighting is the same, if you expand the walls and increase room volume while fixing other variables, the sound produced in that room changes depending on the volume (space) of the room.
So, I think the relationship between the sensory elements and the gross elements is as follows:
- Space affects sound only, but not touch, sight, taste, and smell.
- Air affects both sound and touch, but not sight, taste, and smell.
- Fire/light affects sound, touch, sight, but not taste and smell.
- Water affects sound, touch, sight, and taste.
- Earth affects sound, touch, sight, taste, and smell.
Is this the right way to relate these?