The phrase a private life is old, and for most of its history it described something that arrived more or less on its own. A person of standing had a public face, presented in particular settings, and behind it a private one that the world simply did not see. The privacy was not constructed. It was the default condition, a consequence of the fact that information did not travel far or last long.

That default has gone. Information now travels easily and lasts indefinitely, and the result is that the private life no longer arrives unbidden. The boundary that once formed by itself, between what the world saw and what it did not, must now be drawn deliberately, or it will not be drawn at all. This is the central change, and it is easy to underestimate because the words have stayed the same while the thing they describe has altered completely.

The meaning of a private life is still the right one. It never meant secrecy, in the sense of having things to hide. It meant proportion: that the ordinary business of a person's life, their home, their family, their routine, their affairs, was conducted without being on display, and was known to those who needed to know it and not to others. That is what it still means, and it is still worth having.

What has changed is only that proportion must now be arranged. The records that describe a life are created continually, and they do not respect the old boundary. A person who does nothing will find that the boundary has quietly dissolved, not through any failure of theirs, but because the conditions that used to maintain it no longer exist.

There is a temptation to treat this as a loss and to be wistful about it. That is not quite the right response. The private life is still entirely possible. It is simply no longer free. It now requires the same deliberate attention that other valuable and unguaranteed things require, and a person who gives it that attention can have it as fully as anyone ever did.

To understand what a private life used to mean, then, is not an exercise in nostalgia. It is a way of being clear about the aim. The aim has not changed: proportion, not secrecy; a life known to those it should be known to. Only the means have changed, from a default that could be relied upon to a result that must be produced.