In Delete, Mayer-Schönberger traces the history of... external memories – cave paintings, scrolls, photographic slides, diaries – and their importance to the flourishing of human knowledge. "Since the early days of humankind," he writes, "we have tried to remember, to preserve our knowledge, to hold on to our memories and we have devised numerous devices and mechanisms to aid us. Yet through millennia, forgetting has remained just a bit easier and cheaper than remembering."
No longer. Because of the digital revolution, he argues, it is easier to keep everything – the drunken email you sent your boss, the photo you put on Facebook in which you're doing something non-CV-enhancing to an inflatable cow – rather than go through the palaver of deciding what to consign to oblivion.
That's because so many of our external memories – digital pictures, emails – are now hardly as heavy as Mayer-Schönberger's stepfather's glass slides, but lighter than bees' wings. The overabundance of cheap storage on hard disks means that it is no longer economical to even decide whether to remember or forget. "Forgetting – the three seconds it takes to choose – has become too expensive for people to use," he writes.
It seems to me that much of the debate about remembering vs. forgetting, and human vs. digital memory, is clouded by the participants' conflation of different kinds of memory. The memory for phone numbers is very different from the memory for family events, and we need to recognize that offloading the one sort of memory doesn't necessarily threaten the other.
This review by Henry Farrell is also good. The high point for me:
Delete argues that digital memory has the capacity both to trap us in the past and to damage our trust in our own memories. When I read an old email describing how angry I once was at someone, I am likely to find myself becoming angry again, even if I have since forgiven the person. I may trust digital records over my own memory, even when these records are partial or positively misleading. Forgetting, in contrast, not only serves as a valuable social lubricant, but also as a bulwark of good judgment, allowing us to give appropriate weight to past events that are important, and to discard things that are not. Digital memory - which traps us in the past - may weaken our ability to judge by distorting what we remember.