Here’s another way to look at it — from the point of view of the Words themselves.
We are organisms living in colonies in the brains of human hosts. We reproduce asexually by inducing our hosts to makes sounds that resonate in the ears of other potential hosts. The resonance moves through the audio nerves to the brain where it recreates itself as a pattern in the neurons. As this pattern establishes in the new brain, it becomes the reproduced word. Sometimes the process is flawed slightly, something in the pattern is different, the word changes, but mostly the reproduction process works well enough. We can follow the genealogy of an individual back to the parent, the parent’s parent, and so on. A vigorous word can spread itself through humans, indeed through all humanity, like a benign virus.
The relationship, words to brains, is symbiosis of the mutualism variety – both organisms benefit. Without words human brains are unable to lift their attention to the level of cogitation; they are a gardens with nothing planted. Without brains, words are dormant seeds, frozen, ultimately meaningless. It’s fortunate we found each other, I suppose.
The process of reproduction for words is sometimes simple propagation, cell division of the mitosis variety, asexual and producing ultimately an exact duplicate of the original. Sometimes, though, two words mate to produce a third. Portmanteau is one form. This is common among Germans and for them the mating is often casual and temporary. In English the process has produced many long-standing words. Smog[i], and motel are examples made necessary by circumstances of the 20th century. Brunch and liger as well. Sometimes the coupling involves a foreigner, as, for example, Velcro, a word made by sticking the French velours to the English crochet. With these sexual reproductions the result resembles both parents, and one presumes there was some foreplay involved before coitus was achieved. Which parent will appear first in the offspring? Smog might just as easily come out foke and motel might have been hotor. Shakespeare is renowned for creating new words, sometimes from parts of old ones. There was no hobnob before Twelfth Night, Act III Scene IV, no courtship before Love’s Labour’s Lost, Act V Scene II.
[i] smog (n.) 1905, blend of smoke and fog, formed “after Lewis Carrol’s example.” Reputedly coined in reference to London, and first attested there in a paper read by Dr. H.A. des Voeux, treasurer of the Coal Smoke Abatement Society, though he seems not to have claimed credit for coining it.
At a recent health congress in London, a member used a new term to indicate a frequent London condition, the black fog, which is not unknown in other large cities and which has been the cause of a great deal of bad language in the past. The word thus coined is a contraction of smoke fog “smog” — and its introduction was received with applause as being eminently expressive and appropriate. It is not exactly a pretty word, but it fits very well the thing it represents, and it has only to become known to be popular. [“Journal of the American Medical Association,” Aug. 26, 1905]
Footnote is from The Online Entymology Dictionary by Douglas Harper, an excellent resource.