Chakras are psychic centres in the body that are active at all times, whether we are conscious of them or not. Energy moves through the chakras to produce different psychic states. Modern biological science explains this as the chemical changes produced by the endocrine glands, ductless glands whose secretions mix into the body's bloodstream directly and instantaneously. Ancient philosophers of the East related those changes with the five basic tattvas , or elements- earth, water, fire, air and akasha ( ether ). These elements are constantly coming and going with the circadian rhythms inside the body. The ancient Indian science of Yoga therefore laid great emphasis on knowing these elements and on working accordingly, for the chakras are understood as the playground of the elements. In the ancient science of Svara Yoga (the yoga of conscious breathing), various methods to identify the presence of the tattva in the body are prescribed and by mastering these techniques yogis can program themselves so as to accomplish much by using the least possible amount of energy. By the constant practice of kshata chakra bhedana (piercing the six chakras by visualization) and mantra japa (mantra recitation), they can finally transcend the tattvas, which dominate the five basic centers of the body-that is, the first five chakras-and thereby achieve the nondual consciousness that liberates them from the illusory world of maya.