Three time scales or orders of time are obvious. Two are controversial. And one, measured in microseconds, has only been discovered by the technology of recording, and is not obvious at all.

The obvious time scales are those of:

• The sounds in words and words in sentences, measured in seconds;
• Children’s acquisition of speech and language, measured in days, weeks, months, and years;
• Generations with grandparents often complaining that they can’t understand young people.

Controversially, non-obviously:

• By one of the controversial time scales, the speech and language faculty has evolved as the most complex entity known to science, by the proposal here, completed in seven steps, the last, by the most recent estimate, around 135,000 yearas ago;
• Also controversially, the evolutionary time scale is different from the time scale by what is known as ‘grammaticalisation’ with words like French le forming from Latin ille over hundreds of years;
• A non-obvious time scale applies to the articulation of speech sounds with a fraction of second delay between the opening of the lips in pea, tea, and key, and the adjustment of the vocal cords which forms a vowel. This delay varies across both English and French, increasing from South to North, so that the French name, Thierry, can sound like English Jerry. This differentiaties tea in the North of England from tea in the South, in ways that critically define the speaker’s sense of personal identity. By the proposal here, these differences are encoded by the point in the derivational sequence at which voicing, or the differences between P and B, T, and D, K and G, are defined.

The timing of the gestures in P, T, and K, is well-learnt long before the end of what Eric Lenneberg in 1967 called the ‘critical period for language acquisition’ at around ten. This timing is not easily modified.

The generational time scale may be just a magnifying glass on the grammaticalisation time scale, like King Alfred’s Old English turning into modern English over 1,200 years. What one generation calls a gramophone, another generation may call a turn table or record deck. In current London English, go is used meaning say, isn’t it or innit is becoming a word, like is used to introduce a sentence. But the sounds themselves may be changing at the same time. R may be becoming a sound like W and Y, only used before a vowel, as opposed to a sound like L, used before or after a vowel, always next to it. The changes in the words are obvious. But the changes in the sounds may be detectable too. As these changes are multiplied with one another, one language, over a long enough period of time, turns into a different language.measured in tens or hundreds of thousands of years, is critically relevant to the shortest, the dialectal one, measured in micro-seconds. This short time scale is critically relevant to normal speech and languages acquisition.

Acquisition and grammaticalisation

For parents the process of acquisition may seem prolonged as the first babbles give way to first single words and then sentences. But this is intantaneous by contrast with the process by which languages gradually change, gaining or losing such things as ways of expressing respect for or familiarity with whoever one happens to be talking to. Most varieties of English have completely lost the marking of respect. British Sign Language marks this by the set of the head, slightly raised as a marker of respect, in a way similar to the marking of respect or familiarity by different words for you in every other currently spoken language in Europe and Southern Asia. The loss of this in most varieties of English has taken 400 or so years. The grammar of asking questions and negation was already changing 400 years ago, but also by a relatively drawn out process. In this way, modern English evolved from the language of Shakespeare, as that evolved from the English of Geoffrey Chaucer 600 years ago, as that evolved from the Old English of King Alfred another 600 years earlier. In a similar way, French le and la developed by a process known as grammaticalisation from the Latin ille and illa of Roman soldiers between the fifth century and the early Middle Ages.

By the proposal here, the time scale for the evolution of language is another story, one that involves a different order of magnitude.

Grammar and evolution

By the proposal here, the slowest of these time scales, the evolutionary one, the encoding and fixation of the grammar as a species-universal property must have been a process oover hundreds of thousands of years.

There is a view that the time scales by grammatical change and by the evolution of speech and language are not qualitatively different, that the grammar of ‘Proto-Indo-European’, as it is known, spoken somewhere near the Black Sea perhaps 6,500 years ago, was a step closer to primordial forms of language than any of its modern descendants in the main languages from Europe to Iran, Pakistan, Bangladesh and Northern India. This seems wrong to me. Like José Luis Mendívil Giró (2019), I believe that in order to explain the emergence of the structures, the features, and so on, there have to be different orders of time. As I propose in Order, disorder and evolution and the proposal here, this makes a big difference to the understanding and treatment of developmental disorders.