Self-Control (yama) involves honesty, abstinence, avoidance of theft, refusal of gifts, and not harming living things. Religious Observance (niyama) welcomes poverty, contentment, and devoted reliance on the Supreme Being. Postures (asana), of which there are many, are considered basic to all the stages that follow. Regulation of the Breath (pranayama) includes altering its depth and rhythm and the virtual suspension of breath. Restraint of the Senses (pratyahara) means withdrawing from outside objects and turning the mind upon itself. Steadying of the Mind (dharana) focuses to one part of the body, rendering the practitioner oblivious to outside disturbance. Meditation (dhyana) fixes the mind on the object of knowledge to the point of excluding all other thoughts. Profound Comtemplation (samadhi) is the complete absorption of thought in the object of knowledge, it is uniting with your authentic self. This achievement liberates the self from the illusions of sense and the contradiction of reason. It leads to inner illumination, the true knowledge of reality.The final stage of Yoga doctrine is difficult to attain. Usually, several separations are needed. One from the world of phenomena, then from thoughts of self, and then from the spirit's entanglement with matter. The separation of spirit from matter is true liberation, or Kaivalya.
Some believe this true liberation leads to remarkable abilities. Such as becoming insensible to heat, cold, injury, pleasure, or pain. Basically, it is "mind over matter," which is not an uncommon belief today.