I wrote earlier,
Our biology seems to contain a necessary degree of mutation, even deleterious mutation
Being as we are within time and hence becoming, change is embedded within our mortal being. My personal belief is that the creator/God constructed our universe by fixed principles, e.g. natural selection, but intervenes from time to time: like the theist watchmaker, but one who occasionally opens up the case and oils a cog, blows dust out, or even replaces parts. One can, therefore, see our world as mechanistic or as the object of an interventionist god, depending upon one’s inclination.
Mutation I see as one of the fixed principles, a process by which our reality maintains itself against dissolution. This may seem counter-intuitive, since mutation often enough is an entropic agent, e.g. the development of viruses or freaks:

– but I think a degree of random mutation is necessary, in an imperfect world. Were there no human mutation, then a threat could be engineered, or naturally arise, which could exterminate the entire human race; but with random mutations, it is likely that anything except massive physical force, e.g. a 100 km-wide meteor collision, would leave some mutants untouched. A virus could wipe out 99.999% of humanity, but some mutants would by chance have a genetic invulnerability to just that threat.
Provided there is, around the core human type, a penumbra of random oddities, there is a good chance some of them will be able to survive; they may even contribute something to the benefit of their fellows; and such mutants we could call geniuses.

A few years ago, a German told me that younger children are often the opposite of their elder siblings; she related a theory that the younger see a certain “role” as already occupied, so if their elder brother/sister is wild and emotional the younger will choose to be well-behaved and cool; or vice versa.
I have observed such a phenomenon. However, I think it is at heart a genetic process; I have no idea how, genetically, it would be possible, but I think that each child is created with a certain behavioural tendency, reinforced with appropriate cognitive abilities & defects; and that the mother’s reproductive system will tend to go for an opposite or at least divergent set of attributes with the second child. For example, one of my friends is a little autistic, highly intelligent, thin, tall, and physically weak (he works as a research scientist); and his 4-year younger brother is utterly normal, unintelligent, not so tall, and works as a truck driver.
On the face of it, it seems odd that the mother’s reproductive system would produce two such divergent children; but I think it makes sense as a group survival strategy: if Child A has the genetically successful formula, and survives & has many children, and Child B dies young or childless, then the mother has still produced some grandchildren; if Child A dies childless, then it is likely that Child B would reproduce, since Child B has a totally different behavioural/physical set of characteristics.
So in this scenario, at least one child is likely to reproduce.
However, if Child A and Child B have identical, or similar, attributes, then we have two likely outcomes:
i) Both successfully reproduce and their mother has twice as many grandchildren.
ii) Neither reproduce and the mother’s genetic line ends with them.
In the divergent sibling scenario, there is a high probability of at least some grandchildren; in the similar sibling scenario there is a bimodal outcome: either twice as many, or none at all. Any reasonable gambler would opt for the high probability of some return, rather than a 50-50 win/lose where loss is absolute.
Taking this to a societal level, this could explain why there are always some non-reproductive human beings (the solitary genius, like Tesla or Kafka, or homosexuals) and even what Michael Woodley calls spiteful mutants. Since no society will ever be 100% robust against external threat, mutation is necessary to maintain the hurly-burly of things, where ideas and groups compete, to hopefully produce a healthier society. Without the outlying freak, society would lack the stressors to achieve greatness or resist a true threat:
Like the fella says, in Italy for 30 years under the Borgias they had warfare, terror, murder, and bloodshed, but they produced Michelangelo, Leonardo da Vinci, and the Renaissance. In Switzerland they had brotherly love – they had 500 years of democracy and peace, and what did that produce? The cuckoo clock.
At present in the West, we see the rise of the spiteful mutants to positions of high power; indeed, those who would once have been burnt at the stake or at the last shunned & despised, are now police commissioners, District Attorneys, politicians, media stars, billionaires, journalists. There is presently a war between the mutants and the healthy, with the former occupying most of the positions of power; and attempting to push their own aberrance as normative.
One could see the loathing many feel for Donald Trump as the instinctive hatred the spiteful mutant holds towards the normal – Trump being, in spite of his intelligence & money, in many ways thoroughly normal, a meat & potatoes kind of man; and one who insistently points out that the mutants are the minority, and should not rule.
