Quote from : Red Mars Book

The intense thereness of it-haecceity Sax had called it once, when John had asked him something about his religious beliefs-I believe in haecceity, Sax had said, in thisness, in here-and-nowness, in the particular individuality of every moment. That's why I want to know what is this? what is this? what is this? Now, remembering Sax's odd word and his odd religion, John finally understood him; because he was feeling the thisness of the moment like a rock in his hand, and it felt as if his entire life had been lived only to get him to this moment.