Cloud computing and low-powered sensors has helped usher it in; but it's been around it's just getting more pervasive and interpersonal...

This is what INTEL was pointing to within CA back in 2012-13:

''The Nunchi technology also supports enhanced levels of privacy protection by reacting to user individualities to deliver enhanced privacy and security for users''

Assigning authentications based on habits.

I'll see if can dig it up

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