 This list constitutes a basic analysis of the Classical Notion of sense data.  Item (1)  says that sense data are not perceived by the mediation of anything else. This was often put by saying that sense data are the immediate objects of acts of sensing.  Item (2)  states that our mental relation to sense data is one of direct acquaintance.  (3)  says that if we immediately sense a brown patch of a certain shape, we are acquainted with an item that has the phenomenal brownness and the shape as present in our experience. That is, however color may be considered in physical science (as a microphysical property of object surfaces, for instance), the sense datum possesses the phenomenally present color property.  (4)  indicates that such properties are experienced as determinate; for example, we experience a specific shade of brown.  Item (5)  distinguishes the awareness of sensory qualities such as color and shape from the judgment or affirmation that a material object (or other entity) might underlie the sense datum.  (6)  claims that each perceiver is certain about, and, in a stronger version, cannot err about, there being an instance of brown color of a certain shape that is experienced.  (7)  holds that sense data are private, or perhaps that they inhabit a private space, so that sense data can be related to one another for one perceiver, but the sense data of one perceiver are not in an immediate relation to the sense data of another.  (8)  says that sense data are distinct from the mental acts by which we perceive them; in the Classical Notion, this typically included that they are not mind-dependent but are independent items.