Traditional Indian philosophy has 6 branches or approaches, known as the upangas or darshanas. Often they’re seen as competing philosophical systems when if fact they largely each describe the reality of a different stage of development.
I’ve talked some about several of them, including:
Vaisheshika and Samkhya
Vedanta or end of the Veda (Brahma Sutra, Bhagavad Gita, Upanishads)
Nyaya is the system of logic that informs the others.
One I’ve only touched on is Karma Mimamsa, also known as Purva Mimamsa. Karma Mimamsa means an investigation or reflection on the field of action aka creation. Purva means before. This is a reference to it relative to Uttara (after) Mimamsa, another name for Vedanta.
Karma Mimamsa was written by Jaimini, also known for his text on Jyotish, the science of light aka Vedic astrology. KM is the largest core text of the 6 systems (the table of contents is 44 pages). It is also probably the oldest and least understood.
Today, it is seen as a “forgotten” text. Scholars say it’s missing context but suggest it discusses ritual and duty (dharma).
When Buddha arose, ritual had devolved into behaviors without connection to source. He rejected the rituals, bringing understanding back to the core principles. Approaches like the Karma Mimamsa fell out of favour and faded.
Today, the Karma Mimamsa is understood to suggest that material life is infinite and eternal and cannot be escaped (no liberation) so we may as well make the best of it. I can probably dismiss this was the intention of Jaimini.
While I’m certainly no expert, the text makes more sense if it’s seen in relationship to the other systems. Yoga is fundamentally about liberation – awakening. Vedanta is about Unity. Prior to Vedanta is Purva Mimamsa. We can thus see that the Karma Mimamsa deals with the refinement stage and unfolding awareness of the full range of material life.
This is the arena of Karma Mimamsa although you wouldn’t know it from reading one of the very rare and old translations. The opening sukta seems to be making the point that just because something is invisible doesn’t mean it’s not in the field of action. Essentially, it is pointing to name and form. (sound or vibration becomes form)
Like the Brahma Sutra, there are no translations I can recommend. In fact, most of the books on the topic on Amazon are reprints of an old post-copyright book about the sutra (by AB Keith), not the sutra themselves. One is the sutra in Sanskrit only.
I look forward to the day when decent translations become available. There is what should be an excellent translation of the Brahma Sutra that will eventually be published. It was translated during the late 60’s to early 70’s, as described in the 2 volume series Conversations with Maharishi. I know of no such work on the Karma Mimamsa though. I won’t hold my breath.