One of the worst things that I think you can say to a new parent is “It goes by so fast, enjoy it!” When you have a newborn baby, time is one of those human constructs that goes out the window first. You’re in survival mode—for both you and the baby.

In fact, it’s babies that most convince me that time is one of the things that human consciousness grapples to understand the most, yet understands the least. Sure, it is natural for us to go through the days and weeks in cycles—sleeping at night and having a routine in our days. But no one tells a newborn that. I have four kids, and I’m fairly confident that with each of them in the first few months of life, I took them to the window in the wee hours of the night, pointed outside, and said, “Look. It’s nighttime. This is when you’re supposed to be sleeping,” only to be met with a blank stare. Or maybe some questionable intestinal sounds.

And that is why it can be especially cruel to point out to new parents, who are just trying to survive hour by hour, minute by minute, on little-to-no-sleep, clothing of questionable cleanliness, and certainly no personal hygiene routine, that they will “miss this one day.” Perhaps they will, but even if you’re right, now is not the time. When you’re fighting for survival, reminders of time aren’t helpful. In fact, that can hurt your ability to see what’s right in front of you.

There’s another phrase people say when talking about parenthood that I also think applies more broadly to the human desire and failure to grapple with time. “The days are long, but the years are short.” This at least acknowledges the fact that days can be hard. Making meals, dealing with tantrums, band-aiding cut knees. The daily life of families makes for long days, ending up (often) in exhausted parents who are in bed minutes after the children are. And yes, as the kids grow and go off to school, play sports, spend more time with friends than at home, you can be nostalgic for the time they were more dependent on you for their every need. But two things can be true: that nostalgia and the fact that it is hard, damn hard, to have another human being rely on you that way.

Those two clichés—“It goes by so fast” and “The days are long but the years are short”—aren’t the only clichés about time. In fact, humans have been grappling with the passage of time for so long that I think it may account for some of the oldest clichés in the book. It’s challenging to pin down why time is such an obsession of the human mind. Perhaps it is what comes with a consciousness that is capable of understanding its own mortality. Knowing that a resource is finite causes any animal—human or not—to hoard and obsess over it.

With the consciousness of time comes another feeling. One that, for someone like me who is prone to a significant amount of anxiety, can be more devastating still. Anticipation. And yet another time cliché comes to mind whenever I think of that anticipation: hurry up and wait. Well…I can’t wait.

It’s difficult to decide what is worse to wait for—something good or something bad. In your adult life, you find many of both. A long-awaited vacation. Results of a biopsy. Visits from friends. The next shoe to drop at work. A big (good) milestone for your child. A big (bad) milestone for your child.

I find that all of these things can be complicated to handle as a creature acutely aware that the time we have to wait for them is, in the end, actually all we have. The pressure to both enjoy the time we have and plan for the future we know is inevitable can be daunting. This can be especially hard when dealing with grief and loss—or anticipating grief and loss. Because what, after all, are we worrying about losing when someone is sick or waiting for news from a doctor? It is time.

The thing that we share with each other. The thing that bonds us to one another. The thing that we only have so much of is - time. Time waits for no one. Time is of the essence. Time is money. Time flies when you’re having fun. Time marches on. Only time will tell. Time is running out. Make time. Kill time.

There’s no time like the present? The only time we have is the present.

And that is perhaps the most disturbing part of it all. We only have the present. Past and future are concepts, but only that. The only time we actually have is right now. That’s what makes having a baby and sending that child to school hard. That’s what makes the daily routine and anticipating the future hard. But it’s also all we have, so we better make the most of it. While we still have the time.