"I'd like to propose that mindfulness — true-blue mindfulness — is the open heart. Sure, the purists can define mindfulness as 'paying attention to the present moment with an open and curious stance,' but that definition can be staid, sort of dull, and it can inadvertently take the heart out of a practice, which is, in truth, all heart.

"I remember in my early years of mindfulness practice I got attached to subtle mental states of concentration. I was intensely curious and amazed by my mind, but secretly I felt the practice was a little dry — too much in the head. So I spent a few years seeking out gurus in India, hoping for a devotional hit to make my practice juicier. I later realized I was looking for love in all the wrong places — outside myself instead of inside.

"That's when I discovered that mindfulness practice itself is the open heart. And here's how it works: First you start out on the cushion (or chair for the less pretzelly inclined), and you attend to your present moment experience, no matter what it is — good, bad, or ugly. And as you practice and get some skill — Hey, I can sit here and be okay in the midst of knee pain, in the midst of my aching back, my frayed nerves — then you realize just this: the capacity to be mindful means having an open heart. It's not a theory, it's a heart/body-felt insight.

"Why is this so? Because as you sit there, hour after hour, you learn to say yes. Yes to your jagged breathing, yes to your itchy scalp. Yes to the leaf-blower dude across the street, yes to your grief and pain and shame and grandiosity and fear. Not because you want to act on these things, but because they're true and fleeting and simply part of who you are (but not the half of who you really are). Your nervous system begins to relax — at last you're acknowledging the truth of things.

"Saying yes means attending to and surrendering to your experience, whatever it is. It means feeling your body when you're in the midst of a strong reaction or emotion and letting whatever you find be there. It means coming back to your breath again and again. It means noticing that thoughts and feelings and sensations come and go.

"You say yes to your pride, your stupidity, your murderous rage. Naturally you don't act on your murderous rage, but you allow it to be true within you. It is a very inclusive practice. Nothing is ever left out.

"You discover that if you are pushing away your experience, even ever so slightly, your mindfulness is not fully realized, not quite formed. It is tainted by aversion, even just subtly. Now sometimes you truly can't say yes, and then you say yes to the no: I hate that I'm not feeling okay, but I'm actually okay with not being okay.

"Saying yes in mindfulness practice eventually begins to spill over into your everyday experience. You start to say yes — with awareness — again and again: yes when that guy cuts you off in traffic; yes when your e-mail box is spammed to the brim; yes when your doctor is an hour late; yes even when you lose a treasured person, place, or thing. You say yes to your experience of the present moment, whatever it is. You no longer reject and armor your heart. Not that you necessarily agree with the moment or would wish it on anyone or think it's desirable or wouldn't try to rectify injustice, but you say yes because whatever life brings is just that, life as it is. And by saying yes, you let go deep down inside and can step forward with poise and balance and clarity to the next right thing.

"My six-month-old daughter has been waking me up hourly to night-nurse. Sometimes I say no. Oh god, not again. What's wrong with her? Will I ever get to sleep again? In those moments, mindfulness is a vague 'good idea' somewhere in my sleep-deprived brain. But other nights when she cries, I simply, without thought, say yes. Yes, darling, feast. Yes, I'll be with you. Yes, I'm awake, and that's just how things are. I listen to the stillness of the night (rare in Los Angeles), feel her warm body and attend to her snuffling slurps, and sigh that yes, this is life. A deep peace sets in over me.

"By doing this practice of yes, by mindfully embracing each moment with a willingness to accept things as they are, with a willingness to be with life — inner and outer — exactly as it unfolds, you may be able to look down at your chest and realize that your heart is gigantic. It's expansive, spacious, broken open, like a big, fat suitcase overflowing with warm, comfy, oh-so-familiar clothes.

"You open and open, you attend and attend, you say yes again and again, and then over time, the mindfully opened heart is more and more just who you are."