well approach like that: puthujjanas always do their things from greed, aversion or ignorance. greed and aversion typically refer to kama [opinions, thougths, ideas included], and ignorance to ''non pleasant and non dis pleasant'' feelings, like the non-puthujjana puts it https://www.accesstoinsight.org/tipitaka/mn/mn.044.than.html, or even better to equanimity, especially the 4th jhana. Typically puthujjanas knows nothing about non-kama,and killing ties up to clinging to sensuality [at this point puthujjanas love to talk about their moronic idea of ''survival instincts'' to ''make reasonable'' their toxic deeds and their binary thinking ''it is the other one or me'', ''it is a matter of life or death''] and that clinging to sensuality makes for a miserable life and clinging to sensuality is the only way to not get jhanas and the joy.
Now, the puthujjanas will talk about building something with their life, in order to realize their pathetic fantasy of transcendence, precisely in order to counter the rut and misery of life, precisely because they have zero idea of what they are doing [no matter what they claim] besides following their desires and clinging to kama, to transmit something to '''futur generations'', a society, a lineage, a career and all their idiotic stuff that they build and claim they are good people for building their stuff. The easiest counter point is to make them say that sometimes all the stuff they build is a burden for them, so if it is a burden even one time, then it is not worth doing it [but puthujjanas have no problem with the idea of doing something that does not work, so if this does not work, still no worry, at least one of you two will get tired to talk about that and move on].