Isso é Time Pressure , o segundo na série Lifehouse de Spider Robinson.
Você se lembrou bem perto de corretamente. É realmente a partir do final dos anos 80, mas parece mais antigo, já que o personagem principal, e muitos dos personagens secundários, são hippies.
O argumento decisivo, no entanto:
A abertura do livro tem um prólogo de:
Garanto que cada palavra dessa história é uma mentira.
E um epílogo:
Garanto que cada palavra desta história é a verdade.
Alguns spoilers:
The woman in the story is actually a hybrid of parts of the minds of four characters from the previous book, Mindkiller, two of whom were male. They are beginning on a plot to infect the past with little nano-bots that become resident in every living person, and download all of their life when they die, this download to be stored in an 'Egg' which will then upload it in the future.
The world of the future has seen all of mankind meld together into a mass mind, although remaining discreet individuals, at the same time. With the massive power they have developed, they decide that any human ever having died is a loss, and they are basically trying to retroactively cure death for all of Humanity.
