"The same technology that identifies coughs could also identify laughs..."

Yuval Noah Harari, writing for the Financial Times in The world after coronavirus:

It is crucial to remember that anger, joy, boredom and love are biological phenomena just like fever and a cough. The same technology that identifies coughs could also identify laughs. If corporations and governments start harvesting our biometric data en masse, they can get to know us far better than we know ourselves, and they can then not just predict our feelings but also manipulate our feelings and sell us anything they want — be it a product or a politician.

Linked from Frank.