Some people tell me the heart of fly-fishing lies in the cast. Almost without exception these people are exceptional casters, or at least believe themselves to be.
Others, equally prejudiced, offer the litany of alternatives: The fly is the thing, you see, the substance of the act. Just look at this six-feather masterpiece and tell me otherwise.

Or the fish-when speaking of fish, if you hear mention of colors that don't even show up in the Crayola 264-crayon box (amethyst-flecked this, obsidian-speckled that), there's a person who believes the essence of a pursuit can only lay in its result.
Or the places . . . yes, we're big on places. Surely the soul of the sport lies somewhere near water that burbles, or glides, or runs gin-clear. Mountains are a nice touch, maybe mangroves.

The truth, for me anyway, is simultaneously more and less epic. Less in the sense that I'm staring at a yawning, frighteningly disheveled, obviously hungover fly-fishing guide in western Alaska as I sort through this minor matter of angling metaphysics. He's holding onto his mug of coffee like it's a life raft and there's enough red in his eyes to make one regret not reading Dante more seriously.

"Well," he manages to grumble before heading towards the freshly-scrubbed, frankly jovial bunch awaiting his arrival at the boat, "I'm feeling both rich and rare this morning." I know he's actually talking about the aftereffects of his run-in with a bottle of Canadian hooch the previous night-an altercation he lost convincingly-and I know that for most the word professional probably wouldn't spring to mind. But still I think: Yes, this explains fly-fishing to me.

Now I'm not arguing for a more reductive definition, but rather a more expansive take on the hows and whys of a pastime that frequently burns a fast trail into obsession. It just can't be about the fly or making some pretty loops with a line. On this trip, like with most outings, I had gone noticeably out of my way to get here, spent absurd amounts of money on gear and apparel options that probably didn't need to be updated, and to cast further doubt upon the little integrity I have left, made stunning use of promises I had no intention or probable ability to keep. Fish alone could never have engineered such a complete coup d'tat of my conscience.

It's more epic in the sense that a day-any day-spent on the water carries the potential for transcendence. It's quite a thing to wade into one of these settings where we frequently find our favorite sport fish and from there to discover that we're good enough to succeed in this thing we call life. It's also balanced nicely by the very real prospect of failure, which among other things prevents more bad poetry from being foisted onto the world. Levity helps bridge the gap between the two.

And so it was for me on this trip, when a morning's banner fishing for rainbows was topped off by losing-after twenty minutes, about three feet from shore-the largest rainbow I've ever seen in this drainage. On another day it was coho hand-over-fist until I'd lost interest in ever hooking another, though I could still take much pleasure in watching photographer Dusan Smetana transform into some kind of gill-slitting barbarian who referred to himself in the third person, and only then as 'the Provider.' The fishing in all its forms-frustration, gluttonous success, in the rain, under a sweating sun-was rounded out by the staples of wilderness-camp life: The substantial meals and relaxed, quality conversation, coffee that somehow tastes better in the fog, a humming lantern, waders that smell like roadkill in an advanced stage of decay, the loudest mosquito in the world lodged in my ear for the duration of an entire night. Then on the last evening, after the rest of the clients had wandered off to their tents, it was time for the guides to gather on a gravel bar across from camp and throw horseshoes, talk nonsense and look for the bottom of several bottles of booze. In the last light of another summer day in Alaska, a battery-powered boombox played tunes from someone's Ipod, the camp dogs had a little scrap over a sockeye carcass, at least one person fell in the river and we discussed everything from England's laughable futility in the last World Cup to the shaving of my friend Mike's goatee, a former triumph of hirsute achievement that had once been capable of sending grown men to their knees to weep at its majesty. I laughed and cried, drank too much and stayed up too late, lost at horseshoes but counted victory in several debates.

In the morning, watching the guide Jeb struggle to cope with the excess of the night before, I realized it was these ancillary details and not the mere angling that had affected what Shakespeare called "a sea-change into something rich and strange." I would remember this, and that in the end represents the best of fly-fishing to me, the promise of an experience, not a fish. That such occasions are rare as well is what really keeps me coming back.