This thread reminded me of something from chinese cultural art, a famous piece called, “The Vinegar Tasters.”
The picture consists of three men standing around a pot and each tasting it’s contents. The first man has a sour expression on his face, the second man has a bitter expression, but the the third man is smiling.
Of course the picture is a metaphor. The pot of vinegar represents life. The first man represents Confucious, who thought life on earth was out harmony with “the Way” of heaven and therefore a sour state of affairs.
The second man represents Buddha, who taught that life is bitter, filled attatchments and desires that ultimately always lead to suffering.
The third man represents Lao Tze, the (some say mythical) founder of Taoism. He is smiling because in his view, the world is neither a horrible nightmarish illusion, nor the chaotic result of man’s “fall from grace,” but simply a lesson to be learned, a rhythm to be felt, a current to followed, etc…
Can anyone guess which is my favorite? 
I wanted to jump in here because I think I can offer a fairly unique persepctive to the discussion. For over five years, I’ve practiced a relatively new technique for male multiple orgasm that is not based on semen retention, but nonetheless enables me to enjoy orgasms as much as I wish without any urge to ejaculate even for days or weeks at a time.
To me, classical semen retention techniques such as Tantra and Taoist Sexual Chi Gung are like the Confucianists, struggling against natural impulse to make things “the way they should be.”
To me, the western technique I learned is much more “natural” in the sense that it teaches men how to fully enjoy their orgasmic potential without having to fight their own bodies in the process. The result is the opportunity to truly be present and orgasmically free with one’s self or one’s partner without having to “think about baseball,” or try to “hold back,” etc. And the length of an encounter no longer hinges on “how long you can hold on,” but rather how much pleasure you both can take.
A sexual encounter can end with both partners fulfilled, rather than dwelling on “what could have been.” Most importantly, the other men I know who have learned this successfully, all say the same thing, ejaculation is totally optional. With this technique, deciding whether to finish an encounter with or without ejaculation is literally as easy as flipping a light switch.
So, regarding sexual desire and fulfillment, I just felt obligated to mention that, like the third man in the painting, I’m usually smiling at every step of the way, whether it’s the anticipation of joining with my wife, the joy of expressing our love and ecstasy, or the lingering afterglow that comes from being together in a way that is so totally open. In my experience (and I know many practitioners of Tantra or similiar techniques would agree) when a couple achieve’s an ecstatic union (or an ecstatic connection with one’s self) feelings of desire, arousal, and pleasure can linger for hours or even days afterward, whether it included ejaculation or not.
So I understand (and used to agree with) Oniranauta’s idea of sex, and ejaculation in particular, being associated with “death.” But I’ve gotta say, my recent experiences have taught me that sex, like dreams and like life, is ultimately what you make of it.
One can say desire only serves to enhace the feeling of separation bewteen one’s self and one’s goal. On the other hand, I’ve often found the old saying, “absence makes the heart grow fonder,” to be not only true but also comforting. So, in keeping with Taoist ideal of balance, I think a little desire mixed with a little satisfation is a wonderful way to go through life. But that’s just me. 
And as for sexual energy and it’s effect on dreams (yes, I actually remembered it’s about dreams, lol) personally I’ve gone lucid a couple hours after ejaculating and when I haven’t done so for over 2 weeks, so I have no idea which is more productive. All I know is traditionally, most cultures see sexual energy as closely connected with mental energy. Some say great leaders usually have strong libidos for this same reason.
Which could lead to an interesting side discussion about Bill Clinton… 
