Through which effect can such an impulse push an individual beyond himself? The little we do know is only the tiniest part of this unfathomable mystery.

Research has tried to understand the basic causes responsible for initiating sexual behaviour in superior animals. Animal experiments have demonstrated the existence of a highly complex system of reflex circuits triggered periodically by hormonal stimulation. Biologists have discovered the circuits of sexual pleasure, and possibly even orgasm, in the brain.

But the real centre of desire, where motivation and tension interact to trigger sexual arousal, remains hidden.

Could it be that the trail of desire will be found in the study of hormones, which play a part in the magic of sexual gratification?

Dopamine, one of the chemical molecules our nerve cells use to transmit their electrical messages, is found in above average quantities in the networks of passion.