Our knowledge of reality cannot be absolute in the sense of being unconditioned by our positioning in time and space. Since, as Martin Heidegger says, there cannot be "a worldless subject" (1962: 144), we can only produce knowledge within our own horizons, horizons already determined for us by our culture and a historical contingency which we both inherit and project into the future. So knowledge is discursively constructed, but it does not follow that it is therefore not knowledge. And there may well be a difference between knowledge of non-signifying objects (the "natural world") and signifying objects ("people"). "Natural" objects do not initiate meanings, while to understand people you to have begin by interpreting the meanings they produce.