"I have nothing to hide" is the most common response to privacy concerns. It misunderstands what data collection does with ordinary, innocent information.
Data outlives its context
Information collected today is judged by the standards of an unknown future. Location history from a period when visiting a particular clinic, attending a particular meeting, or living in a particular neighborhood was unremarkable can become sensitive when laws, governments, or your own circumstances change. You cannot delete data you no longer control, and data brokers resell it indefinitely.
You don't get to decide what's incriminating
Aggregated data supports inferences you never consented to. Purchase history predicts pregnancy. Location data reveals religion (weekly visits to a place of worship), health conditions (repeated visits to a specialist), and relationships (two phones that spend every night at the same address). Insurance pricing, tenant screening, and employment screening increasingly consume this kind of derived data. The question is not whether you have something to hide, but whether strangers should get to draw conclusions about you from data you didn't know you were producing.
Breaches happen to everyone
Every organization that stores your data is a future breach you have no control over. The 2017 Equifax breach exposed Social Security numbers and birth dates for roughly 147 million people who never chose to be Equifax customers.[1] Minimizing what is collected in the first place is the only defense that works retroactively.
Privacy is a collective good
Even if you personally accept surveillance, your contacts did not. Uploading your address book exposes people who never agreed to it. Using end-to-end-encrypted messaging protects the person on the other end of the conversation, not just you. Normalizing encryption also protects the people who need it most (journalists, abuse survivors, activists) because tools used only by people with "something to hide" paint a target on them.
It is not all-or-nothing
The goal is not to disappear. The goal is to stop leaking data you get nothing in return for. Most of the measures in this cookbook cost minutes and remove entire categories of exposure. Start with threat modeling to figure out which ones are worth it for you.
Federal Trade Commission, Equifax Data Breach Settlement. ↩︎