The Pentagon canceled its so-called LifeLog project, an ambitious effort to build a database tracking a person’s entire existence, including just about everything an individual says, sees, or does.

LifeLog’s backers said the all-encompassing diary could have turned into a near-perfect digital memory, giving its users computerized assistants with an almost flawless recall of what they had done in the past. But civil libertarians immediately pounced on the project when it debuted last spring, arguing that LifeLog could become the ultimate tool for profiling potential enemies of the state.

Private-sector research in this area is proceeding. At Microsoft, for example, minicomputer pioneer Gordon Bell’s program, MyLifeBits, continues to develop ways to sort and store memories.