Sri Aurobindo
Letters of Sri Aurobindo
Volume IV - Part 3
The sex-energy utilised by Nature for the purpose of reproduction is in its real nature a fundamental energy of life. It can 
be used not for the heightening but for a certain intensification of the vital emotional life; it can be controlled and diverted from the sex-purpose and used for aesthetic and artistic or other creation and productiveness, or preserved for heightening of the intellectual or other energies. Entirely controlled it can be turned into a force of spiritual energy also. This was well known in ancient India and was described as the conversion of retas into ojas by Brahmacharya. Sex-energy misused turns to disorder and disintegration of the life-energy and its powers.