Nichols explains the migrations out of India ( ie Bactria-margiana ) solely as a function of Geography. The migration *patterns* across Eurasia are overwhelmingly from East to West. Basically, you just need to get a dialect into the steppe expansion zone and this will naturally be carried across into the western cul de sac, leading to a compilation of a pseudo diversity (nongenerative) at the western end. IE, Iranian, turkic, Uralic, and Indic all expand from East to west. When you factor in the sole out-of-africa southern migration route with South Asia serving as a genetic diversification crucible, this only reinforces an overwhelming east to west historical gradient across Eurasia. Hunnic invasions into South Asia are a minor affair (and are nonetheless mostly from the East itself) and do not alter the south asian cultural landscape.
This is the default migration pattern with a non-normative ( heathen ) societal configuration. Any reversal within a non-normative configuration will be minor and will not result in any overwhelming cultural change on the scale of (putative) AIT. Likewise, the emigrant groups from south asia will not experience any ideological dissonance, nor will the receiving groups. of course conflict<i> per se</i> is not precluded (ie the conflict will be heathen type conflict, eg between kings and rulers (and not tribal).
To reverse this general pattern of migrations (which is dependent solely upon geography and the initial populating inoculations), you actually have to reverse the cultural configuration from non-normative to normative. Alexander's invasion was the beginning where there is just a small residue of normativism. Judaism is the first _application_ of Normative ethics as imperial propaganda in the Ptolemaic and Seleucid setting. Christianity is the Roman successor.
This is the default migration pattern with a non-normative ( heathen ) societal configuration. Any reversal within a non-normative configuration will be minor and will not result in any overwhelming cultural change on the scale of (putative) AIT. Likewise, the emigrant groups from south asia will not experience any ideological dissonance, nor will the receiving groups. of course conflict<i> per se</i> is not precluded (ie the conflict will be heathen type conflict, eg between kings and rulers (and not tribal).
To reverse this general pattern of migrations (which is dependent solely upon geography and the initial populating inoculations), you actually have to reverse the cultural configuration from non-normative to normative. Alexander's invasion was the beginning where there is just a small residue of normativism. Judaism is the first _application_ of Normative ethics as imperial propaganda in the Ptolemaic and Seleucid setting. Christianity is the Roman successor.