Kevin Kelly, editor of Wired magazine, created the law in 2007 after being influenced by Pattie Maes at MIT and Joel Garreau (author of Radical Evolution).
[1] In 1993, Maes listed a number of her colleagues at MIT that had publicly predicted mind uploading (the replication of a human brain on a computer), and noted that the innovations were generally slated to occur approximately 70 years after the birth of the predictor.
Three score and ten years from their individual births, technology would be ripe for them to download their consciousnesses into a computer.
They were each, in their own minds, going to be remarkably lucky, to be in just the right place at the right time.The Machine Intelligence Research Institute released a paper detailing a much larger set of 95 AI predictions extracted from a database of 257 AI predictions, which finds a broad array of estimates significantly before and after a predictor's estimated longevity, thus contradicting the law.
MIRI states a stronger rule as being "Maes-Garreau": "the predictor expects AI to be developed at the exact end of their life.