If you are a Prābhākara, you think that students don’t have to learn the Veda and that they actually do it because of the teachers’ duty to teach it. This certainly solves the problem of having a young boy (younger than 8) deciding to study the Veda based on an analysis of the benefits he will get out of this study. Does this also solve the problem of whether one should study also Mīmāṃsā?
In other words, assuming that one learns the Veda due to the prescription to teach it, does this prescription include the duty to teach the meaning? No, says Veṅkaṭanātha in his refutation of the Prābhākara position. Just like the knowledge of the meaning of the Veda is no included in the prescription to learn it by heart, so it is not included in the prescription to teach it. Both stop their function at the Vedic phonemes.
So far so good, but then Veṅkaṭanātha adds an additional reason why the prescription to teach does not reach until the meaning of the Veda, namely:
अबाधितप्रत्ययोत्पत्तावनपेक्षत्वलक्षणप्रामाण्यस्य वक्ष्यमाणत्वाच्च
And because in the case of the coming into being of a cognition which has not been invalidated, we will say that its validity (prāmāṇya) consists in its being independent. (SM ad 1.1.1, 1971 p. 27)
The reference is clearly to PMS 1.1.5, where the Veda is said to be a pramāṇa because it is independent from any other source. That is, once a cognition has indeed come into being and is not sublated, the only thing which could make one doubt about it is its having the wrong source, but if it is independent on any source, no such worry can arise. Why is this said here? Perhaps because a cognition of the meaning does indeed take place upon learning the Veda by heart and unless one can prove that it is wrong, one needs to consider it valid. Hence, the need to study Mīmāṃsā cannot be justified on the basis of the need to understand the meaning of the Veda.