Man seek Sex is a movement of general Nature seeking for its play and it uses this or that one--a man vitally or physically "in love.' as it is called with a woman is simply repeating and satisfying the world-movement of sex; if it had not been that woman, it would have been another .

                            SRI AUROBINDO, On Yoga, 11, tome II, 7

The terrestrial sex-movement is a utilisation by Nature of the fundamental physical energy for the purposes of procreation. The thrill of which the poets speak, which is accompanied by a very gross excitement, is the lure by which she makes the vital consent to this otherwise unpleasing process ; there are numbers who experience a recoil of disgust after the act and repulsion from the partner in it because of the disgust, though they return to it when the disgust has worn off for the sake of this lure.
   The sex energy itself is a great power with two components in its physical basis, one meant for procreation and the process necessary for it, the other for feeding the general energies of the body, mind and vital-also the spiritual energies of the body. The old yogis call these two components retas and ojas.

  It is the ordinary nature of vital love not to last or , if it tries to last, not to satisfy, because it is a passion which Nature has thrown in in order to serve a temporary purpose ; it is good enough therefore for a temporary purpose and its normal tendency is to wane when it has sufficiently served Nature's purpose. In mankind, as man is a more complex being, she calls in the aid of imagination and idealism to help her push, gives a sense of ardour, of beauty and fire and glory, but all that wanes after a time. It cannot last, because it is all a borrowed light and power, borrowed in the sense of being a reflection caught from something beyond and not native to the reflecting vital medium which imagination uses for the purpose. More over, nothing lasts in the mind and vital, all is a flux there. The one thing that endures is the soul, the spirit. Therefore love can last and satisfy only if it bases itself on the soul and spirit, if it has its roots there. But that means living no longer in the vital but in the soul and spirit.

                                SRI AUROBINDO, On Yoga, II, tome I, part 11,7