9.32 Bhagavadgita
māṃ hi pārtha vyapāśritya ye ‘pi syuḥ pāpayonayaḥ striyo vaiśyāstathā śūdrās te’ pi yānti parāṃ gatim
The situation is a bit more complex. The word ‘yoni’ here does much more work than one assumes. All the four are born from ‘Yoni’ but yet are distinguished in terms of punya and paapa. The last two are earnt by the organism in question: ‘svayaarjita’, suggesting that being a brahmana and a rajarshi are earnt titles. As against it, we have a gender and a shudra.
If we realize that every one is a shudra (including ‘brahmins’) until certain ‘samskara’ (not be seen as mere rituals in Sanskrit), we see that ‘stree’ and ‘shudra’ pick out people, who do not do the effort or achieve samskaras. The word ‘stree’ is used to indicate that that we are all born as shudras, the way gender is a biological property. Thus, those remain in the ’natural’ state are paapayoni’s. Those who go beyond this natural state and advance are the rajarshi’s and brahmanas. If you further relaize that ‘rajarshi’ is a recognition that is accorded by other ‘rishis’, then you relaize that so is brahmana. Thus the contrast Gita is making is this: if you remain the way you are born without doing any further effort, then you are a paapayoni; if you put in the effort to grow, then you are a punyayoni. To make sure that people would understand this distinction, gita speaks about shudra and stree (two natural properties) and brahamana and rajarshi (two acquired properties). There is more, but thus should be enough to teach people to read, an ability that people appear to have lost these days.