Far too many people are unaware of the real consequences of giving up their privacy. As Carissa Véliz writes, privacy is not a private issue, privacy is a collective issue.
Because we are intertwined in ways that make us vulnerable to each other, we are responsible for each other’s privacy. I might, for instance, be extremely careful with my phone number and physical address. But if you have me as a contact in your mobile phone and then give access to companies to that phone, my privacy will be at risk regardless of the precautions I have taken. This is why you shouldn’t store more sensitive data than necessary in your address book, post photos of others without their permission, or even expose your own privacy unnecessarily. When you expose information about yourself, you are almost always exposing information about others.