Madhvaon Brahma Sūtra 1.4.20

In order that the initial statement, “ There is no way leading unto the Lord other (than knowledge)”, may be- come proved (be clearly brought home to our minds), Asmarathya is of opinion that (by scripture) sacrificial duties, etc., are described (at great length) as an argument; for (the world shall thereby know) that all this leads to perishable fruits (of short duration), and be convinced of the truth of the initial statement “ there is no way, etc.” (From another point of view, the usefulness of the description of Karma, etc., towards the knowledge of Brahman, is explained by the following Sutra).