The main project of yoga is to ground us in reality so that we might be aware of the experience of truth. The truth is now; in the present moment. There is not other reality. The past and the future are merely mirages in the distance. We cannot be sure of either, though on some level, everything that takes form in nature or in our minds has some level of truth to it. As yogis our task is to recognize the truth and keep our awareness fixed there.