Indirect Realism
A theory of perception where sense data, mental representations of objects, mediate our awareness of mind-independent objects.
Sense Data
Mental representations experienced of the object of perception, distinct from mind-independent objects and are mind-dependent.
Fallible Knowledge
Understanding in indirect realism where knowledge of mind-independent objects is inferred from sense data, making it potentially erroneous.
Immediate Perception
Indirect realists view perception as indirect due to the causal chain involved in becoming aware of sense data.
Veil of Perception
Sense data in indirect realism are described as a barrier between the mind's eye and the mind-independent world.
Naïve Direct Realism
Belief that we directly perceive mind-independent objects without mediation, challenged by the argument from illusion.
Philosophical Direct Realism
The belief that we directly perceive mind-independent objects in the external world, rather than sense data representing these objects.
Relational Properties
Properties that exist in the interaction between a mind-independent object and the subject of perception, such as the perceptual variations of an object due to perspective.
Hallucination
Perceiving something that does not mind-independently exist, leading to the conclusion that what is perceived must be mental sense-data.
Time-lag in Perception
The delay between an event happening in the mind-independent world and its perception due to factors like the finite speed of light, suggesting indirect perception of the external world.
Indirect Realism
Philosophers like John Locke and Bertrand Russell argue that our access to the mind-independent world is always indirect, through inferences from knowledge of mind-dependent sense data.
Primary Qualities
Qualities such as extension, shape, motion, number, and solidity that are measurable objectively and inseparable from the mind-independent object, as proposed by Locke to support indirect realism.
Secondary Qualities
Qualities like color, taste, smell, and temperature that arise from the interaction of the mind-independent object and the subject of perception, not essential to the existence of the object, contrasting with primary qualities.