Tathata (Sanskrit: तथाता) a central concept in Eastern religions, is translated as "thusness" or "suchness”. It is related to the perception of the present moment, of the reality expressed in each unique moment, for no moment is same as the other.
In the Flower Sermon, the Buddha propogated, "We know we are experiencing the 'thatness' of reality when we experience something and say to ourselves, 'Yes, that's it; that is the way things are.' In the moment, we recognize that reality is wondrously beautiful but also that its patterns are fragile and passing."
The Buddha’s Enlightenment is the attainment of this state of "suchness" or "thusness” where one is able to perceive things as they "really" are. In the state of Tathata, the enlightened person understands that things not in reality, but only through human perception and language.