It is said here that the sages reached the transcendental spiritual sky by dint of their mystic power. That is the perfection of the yoga system. The breathing exercises and disciplines to keep health in proper order are not the ultimate goals of yoga perfection. The yoga system as generally understood is ashtanga-yoga, or siddhi, eightfold perfection in yoga. By dint of perfection in yoga one can become lighter than the lightest and heavier than the heaviest; one can go wherever he likes and can achieve opulences as he likes. There are eight such perfections. The rishis, the four Kumaras, reached Vaikuntha by becoming lighter than the lightest and thus passing over the space of the material world. Modern mechanical space vehicles are unsuccessful because they cannot go to the highest region of this material creation, and they certainly cannot enter the spiritual sky.

But by perfection of the yoga system one not only can travel through material space, but can surpass material space and enter the spiritual sky. We learn this fact also from an incident concerning Durvasa Muni and Maharaja Ambarisha. It is understood that in one year Durvasa Muni traveled everywhere and went into the spiritual sky to meet the Supreme Personality of Godhead, Narayana. By present standards, scientists calculate that if one could travel at the speed of light, it would take forty thousand years to reach the highest planet of this material world. But the yoga system can carry one without limitation or difficulty.