Yesterday I wrote about how I keep my diaries. This morning, because commenters asked what they look like, I posted some of my diary pages on Instagram. Then a commenter asked, “But what is the point of this?”

Here’s what I wrote back, verbatim:

I keep a diary for many reasons, but the main one is: It helps me pay attention to my life. By sitting down and writing about my life, I pay attention to it, I honor it, and when I’ve written about it long enough, I have a record of my days, and I can then go back and pay attention to what I pay attention to, discover my own patterns, and know myself better. It helps me fall in love with my life.

So, primarily, keeping a diary is about paying attention to my life and then paying attention to what I pay attention to.

There are some other reasons I keep a diary.

I have a terrible memory for things that happen to me. I can remember books and quotes and movies and art and all of these inanimate things that I love, but I simply cannot seem to keep track of my own days. My experience of time is very slippery.

This quality got exacerbated when I had children. Infants destroy your memory through sleep deprivation, but toddlers and preschoolers play tricks on your sense of time and progress when you’re around them all day, because 1) having young children can be extremely monotonous, and 2) you’re seeing them morph in real time, so the change is gradual, and you don’t necessarily take notice of the leaps and bounds that can happen in even a week. (For an alternative perspective, see Sarah Manguso’s Ongoingness: The End of a Diary.)

Diaries are evidence of our days. When I read a diary from even just a few months ago, I am regularly shocked by how much has and hasn’t changed in our house. It helps me take notice of just how far we’ve come. It also reminds me that life is seasonal, and we are inevitably doomed to repeat ourselves, a la Groundhog Day, so we must proceed without hope and without despair.

Finally, I find that my diary is a good place to have bad ideas. I tell my diary everything I shouldn’t tell anybody else, especially everyone on social media. We are in a shitty time in which you can’t really go out on any intellectual limbs publicly, or people — even your so-called friends! — will throw rocks at you or try to saw off the branch. Harsh, but true.

So you have to have a private space to have your own thoughts. A diary does that.

I wonder how many people forget that George Orwell’s 1984 literally begins when the character Winston Smith buys a paper diary and starts writing in it. I’ve heard that part of the goal of an autocratic regime is to get you to disbelieve your own perceptions. Again, here is where your diary comes in handy. You keep track of what’s happening, write your own history book, consult it when you feel like you’re going crazy.