I think I covered this under the topics of Bloodlines, Scientists Wanted and maybe under Western 1st Encounter. The basic unit of life; or as we have come to know it, the cell represents human genesis. It was such for the ancients and it remains so for us. According to scientists there are two types of cell the prokaryote and the eukaryote. Bacteria is listed as prokaryotic and plants and animals i.e. humans, eukaryotic. Among scientists it is generally accepted that the prokaryote preceded the eukaryote on the evolutionary chain, and that the eukaryote exists due to symbiosis among prokaryotes. So at our core/root human beings and bacteria are siblings.
Not all bacteria are parasitic or saprophytic only heterotrophic bacteria behave in such a manner. Autotrophic bacteria produce their own food out of the elements as in photosynthesis. Some Autotrophic bacteria are even able to generate food without the benefit of sunlight, and since humans cannot exist without some sunlight it is highly unlikely that the two would ever occupy the same space but without them we die. Heterotrophic bacteria are ubiquitous, most exist in harmony with plants and animals, are symbiotic and non-pathogenic; but there are some, not the majority although they are more widely known, those behave much like our free radicals and are capable of doing serious injury to plants and animals. For those we require codes of behavior or conduct in a hygenic/social/moral sense; in the political sense this is called rules and regulations, in order that we might co-exist within the same system; without conflict.
To your question on Caste: One might suspect that the poorly shod children of the shoemaker are lazy mongrels. What’s stopping them from emulating their father? They are after all of his seed/cell/eukaryote; and according to all the laws of nature should be just as capable, even more so of creating acceptable footwear. If I grew up in a family of physicians, am I more likely to become a doctor or an actor? The fact remains we become what we know and since civilization evolved out of the family it should not be hard to imagine that societal caste shares the same root.
As always know the universe in yourself, do not look for yourself in the universe for as you can probably already attest it has become a carcass, and we, no more than saprophytic microbes on that carcass; in the end we'll all be dead, for we are what we eat. Unless of course we become less parasitic and more symbiotic.
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