All the data gathered through Pratyaksha Pramanam deal with anaatma (Non-Self) and not with the atma (The Self).

Scientific reasoning is called Laukika (worldly) anumaanam.Laukika anumaanam deals with anatma or apara vidya and has no access to atma vidya. The Kathopanishad confirms: "Naisha tarkena matiraapaneya" i.e. one cannot hope to arrive at the atma through Laukika Anumanam. It is like trying to hear through the eyes. The logic used by shastram is shastreeya anumaanam. While laukika anumaanam is based on data collected through perception, shastreeya anumaanam is dealing with atma or Brahman where the data cannot be collected through observation but is collected from shastram.

We accept the shastram as a valid means of knowledge. The conclusions based on shastric statements can be questioned but the shastram by itself cannot be questioned as we give validity to shastram.

In Brahmasutra we are collecting data from the shastram which we don't question but based on data we are trying to arive at a conclusion to find what is the essential teaching. For the shastreeya pramaanam the basic assumption is that the student must be an astika. But it does not mean that Brahmasutra neglects laukika anumaanam as it is predominantly using shastreeya anumaanam based on upanishads.

The laukika anumaanam used in Brahmasutra is never to establish vedanta. Vedanta arrives at a conclusion through the shastreeya anumaanam. Laukika anumaanam can neither prove nor disprove vedanta. Some (nastika) philosophers use laukika anumaanam to disprove vedanta. Therefore, vedantin uses the laukika anumaanam to show the fallacy of the laukika anumaanam used by other philosophers. Thus, vedanta uses the laukika anumaanam not to prove that vedanta is logical but to prove that vedanta is not illogical.

Both the laukika anumaanam and shastreeya anumaanam depend upon some external data collected through some other pramaanam. Therefore, they are dependent and both do not question the validity of the data. But, laukika anumaanam can deal only with anatma as it is based on perception. Whereas shastreeya anumaanam is based on shastram dealing with atma. This implies that the field of vedanta is diferent from the field of science.

In the first adhyaaya, the shastreeya anumaanam based conclusions are presented and vedanta shows that tarka is not an end by itself and the second adhyaaya shows that the laukika anumaanam is far behind vedanta.

Shankaracharya's commentary on the Brahma Sutra starts with the Adhyasa Bashyam