My 6-year-old son is really farsighted, and I had no idea. I completely missed it.

To be fair to me and my husband, the ophthalmologist (the esteemed and wonderful Dr. Hunter of Children’s Hospital Boston) said that Liam was compensating really well. And until his yearly checkup last month, he had been passing vision tests (which mostly test for nearsightedness). But in retrospect, there were signs we didn’t pay attention to. He didn’t like looking at words in books, and on hikes he kept saying “Where?” when my husband pointed to things nearby. We thought he was impatient or not paying attention. Turns out he couldn’t see.

It got me thinking about humility.

It’s easy for me to think I’ve got this parenting thing down pat. After all, come February I will have been at it for 21 years. I’ve had lots of experience with everything from babies who won’t stop crying to teenagers pushing the limits of independence. I’ve managed countless fevers, homework predicaments, sibling fights, and social crises. I’ve potty-trained five kids, and helped teach them all to read, look both ways before crossing the street, be polite, and eat vegetables. I’ve learned to pick up on the subtle clues of illness, sadness, and fear.

Yet I missed Liam’s farsightedness.  And for the past couple of weeks I’ve been wondering if I missed it because I was too sure of myself as a parent.

It’s the same in medicine. It’s really easy to get sure of yourself as a doctor, especially when you’ve been doing it for a while—and especially when you have lots of patients to see. It’s easy to say: I know this. I’ve seen this before; I know what to do.  Been there, done that.

Usually, it works out. But sometimes, it can make us miss things we should see.

I don’t think that it’s arrogance that gets us into these situations. Well, maybe it’s a little bit of arrogance. Mostly, though, it’s convenience. It’s so much easier to go into things with our assumptions and habits, with our certainty about our experience. It makes us feel more calm, comfortable, and confident—and all of those are good things.

It’s much harder to go into things realizing that every day, every moment, every child or patient is new. Going into everything with a clear eye, mind, and heart is so much more work—and means acknowledging that there is so much we don’t know. In fact, it means focusing on what we don’t know—and who wants to do that?

We tend to think of humility as an optional virtue. Humble people are admirable and all that, but we think of humility as something that can get in the way of excellence and achievement.

But I think that it’s only through humility that we can achieve great things. We might get lucky here and there without it, but it’s only when we know our limits that we can push those limits, and ourselves, further. It’s only with a clear eye, mind, and heart that we can see what we need to see.

Like Liam’s farsightedness.

Claire McCarthy is a primary care physician and the medical director of Children’s Hospital Boston’s Martha Eliot Health Center.  She blogs at Thrive, the Children’s Hospital Boston blog.

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