It could be since Ang Lee is Chinese or Taiwanese! Not that there is any difference.
uh oh! don't let a Taiwanese hear you say that.
They'll give you an earful of differences.
According to wikipedia, "yin" is black and represent a passive, dark, femenine dowright seeking personality. The "yang" (white), is active, light, masculine, upward-seeking and corresponds to the day. Yin is often symbolized by water, while yang is symbolized by fire. So I guess, Jack, who wears the black hat is yin, and Ennis is yang. However, Jack isn't exactly passive in the relationship, but quite the contrary. He isn't downright either but quite upright; always dreaming; Ennis is the exact opposite.
Interesting, downright/upright. There was a thread sometimes back talking aobut how Jack is often in the reclining versus Ennis' upright. For example, the "Tent don't look right" scene, Jack is reclined playing his harmonica, while Ennis is upright. Or Jack is reclined while trying to open the can of beans, while Ennis sits upright tending to hygiene. Even in the opening scene, Jack's tendency to drape himself on the truck, instead of standing on his feet.
but like Amanda and others have said, the men don't stay in passive/aggressive mode all the time. They have a push/pull dynamic, so they both are yin and both are yang at different times. But yes, I definitely thing that the choice of black and white hats are deliberate. Not only on Ennis and Jack, but on other men in the scenes. You think of all the colors of cowboy hats the costume designer could have chosen for the cast and extras, you'd think that there'd be more variety. The use of black and white is overwhelmingly noticeable.
