A Palmistry example in Indian philosophical texts

In Rāmānujācārya's Tantrarahasya, an example echoing palmistry runs as follows:

The being a means to realise what is desired (iṣṭasādhana) does not incite (prayuj-) [one] to undertake an action (pravṛtti), since no undertaking of action is [commonly] seen in regard to present (since one is already eating, no action needs to be undertaken) and past eating, etc., which are a means to realise satisfaction (tṛpti), [and] since even in regard to future means to realise results, such as (auspicious) bodily marks (lakṣ-), which indicate (sūc-) good fortune and are made known by the experts of palmistry (sāmudrika), no action is undertaken (pravṛtti)¹, [and] since, similarly, there is no activation when the means to realise (sādhana) future results, like rain and sunshine (ātapa), depend on fate (daivika).

The same example is found in Śālikanātha's Vākyārthamātṛkā and in Prakāśātman's Śabanirṇaya. In his (still unpublished) translation of the latter, Hugo David mentions also Maṇḍana Miśra's Vidhiviveka, its commentary (Vācaspati Miśra's Nyāyakāṇikā) and Gāṅgeśa. He then refers the latter's explanation, according to which a child, to which a palm-reader has said he will become a king, does not undertake any action, though he desires this destiny and knows all means to achieve it. 

Though this is possible, the passage mentioned above does not favour this interpretation, insofar as palmistry is mentioned as in itself a future means to achieve something desired (bhaviṣyatsv api phalasādhaneṣu). It is not said that someone does not undertake an action in regard to a future result, indicated by fortune tellers. And what would this lack of action point to? Gāṅgeśa just says that one does not always undertake an action in regard to a future result, whereas here the point is the future means of a (necessarily future) result.

 The gist of the passage, opposing bhaviṣyatsu phalasādhaneṣu and bhaviṣyatphalasādhaneṣu seems to indicate that those auspicious marks will become means for the arousal of good fortune, whereas for the time being they just indicate (sūc-) it. In fact, according to the Indian study of bodily marks, bodily marks change throughout one's life according to one's being. Again (but I could not find any direct statement supporting that), those changed marks are the cause of one's good fortune, etc. Still, one does not undertake any activity in order to modify one's bodily signs.