In science, mutation is a modification of a segment of the genome or DNA of an organism.

Chance | Determinism
Of note, mutation in colloquial knowledge, is believed to be blind, random, chance-based, and or accidental; oft-conceptualized as “mistakes”. This, however, is a mistaken view; an issue first broached by Schoffeniels:

Spontaneousmutations’, according to Monad, are regulated by the laws of chance, that is to say, those of large numbers. Now this statement appears to me questionable. Whatever the interpretation, ‘chance’ does not seem to be concerned save if we wish to mask our ignorance for the time being.”
Ernest Schoffeniels (1973), Anti-Chance (pg. 45) [1]

All "spontaneous" changes in atomic structures of DNA are governed by the spontaneity criterion, which is deterministic, and not chance based. This confusion tends to be one of the barriers in the ongoing science vs religion debates and tensions.

Quotes
The following are related quotes:

Science says that a series of genetic mistakes, genetic mutations led to the great complexity of our world.”
— Shmuley Boteach (2009), La Ciudad de las Ideas Re-evolution (vid | 3:58)

References
1. Schoffeniels, Ernest. (1973). Anti-Chance: a Reply to Monod’s Chance and Necessity (L’Anti-Hasard) (Amz) (translator: B.L. Reid) (pg. 20-21). Pergamon, 1976.

External links
Mutation – Wikipedia.

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