When we perceive we are under the impression of being directly aware of concrete, mindindependent objects. We also consider perception as a basic, reliable source for acquiring beliefs and an effective means for coping with the environment. In the philosophical literature, this direct and basic character of perception is sometimes captured by saying that perception is openness to the world. Articulating, refining and vindicating as far as possible this commonsensical view of perception as openness to the world is the main objective of this work. In order to make the metaphor of openness tractable in theoretical terms, I set up the dialectic in terms of a contrast between representationalism, which holds that perception represents things as ...