She started by showing us the rate of change is not constant.
For centuries the norm was rapid change in spoken English. For instance, between the times of Chaucer (fourteenth century) and of Jonathan Swift (early eighteenth century) there was such a massive change that Swift's readers would have had difficulty reading Chaucer.
She read the first lines of the Prologue from Chaucer's The Canterbury Tales - in the accent of the time, I might add!
Whan that April with his showres sooteIn contrast, when she read the opening to Swift's Gulliver's Travels, we had no trouble understanding the text.
The droughte of March hath perced to the roote,
And bathed every veine in swich licour,
Of which vertu engendred is the flowr;
When Zephyrus eek with his sweete breeth
Inspired hath in every holt and heeth
The tendre croppes, and the yonge sonne
Hath in the Ram his halve cours yronne,
And smale fowles maken melodye
That sleepen al the night with open ye -
So priketh hem Nature in hir corages -
Than longen folk to goon on pilgrimages.
My father had a small estate in Nottinghamshire: I was the third of five sons. He sent me to Emanuel College in Cambridge at fourteen years old, where I resided three years, and applied myself close to my studies; but the charge of maintaining me, although I had a very scanty allowance, being too great for a narrow fortune, I was bound apprentice to Mr. James Bates, and eminent surgeon in London, with whom I continued four years.Out of interest, after typing this quote, I spell-checked it, and Word thinks it is acceptable modern grammar.
The rise of written English as the pre-eminent form is the reason behind this slowing of the rate of change. When most business and study and social interaction occurred through spoken English, people didn't mind language changing, as long as they could understand each other. But we, with almost universal literacy, are strongly influenced by the way a word is written, visualising it as we say it, and this makes us resist change.
It was a great talk and has given me lots to think about.