Empiricists recognize the primacy of existence over consciousness as they recognize the non-constitutive character of the subject’s awareness of the objects in the physical realm. Within this scheme, truth is dependent upon the correspondence of the subject’s beliefs in the external world. This recognition of sensory experience as the primary source of knowledge enables the conception of perception as the basis for knowledge acquisition. In this sense, the verifiability of knowledge may be presented through the use of sensory evidence.
This is in direct opposition to the propositional based method of knowledge justification [as it uses perception as a method of knowledge acquisition]. Knowledge presupposes both existence and consciousness. This is based on the intuitive assumption that the primacy of existence should be accepted as a foundation for knowledge formation since it is implicit in any instance of awareness evident in its affirmation even during instances of denying it. This claim leads to the epistemological character of consciousness which leaves consciousness totally dependent on existence for its content.
This dependence is due to the object’s possession of identity independent of the perceiver’s consciousness and to the mind’s sole function of grasping entities in the physical realm. Perception, in this sense, may be understood as “the direct awareness of discriminated entities by means of patterns of energy absorption of sense receptors” (Kelley, 1986, p. 144). Perception, in this sense, involves the awareness of the object as a unit or entity. Such awareness is possible through the absorption of energy by the sense receptors.
A sensation cannot be mistaken as a perception for perceptions involve the awareness of the entity itself and not the singular attributes of the entity. Specificity is necessary in order to account for perceptual discrimination. Discrimination refers to the isolation of the object from its background which is based upon its qualitative difference from other objects in the perceptual field. Continuous discrimination allows an individual to shift from a naive level of realism to a scientific level of realism.
The progression from one level to another is enabled by the individual’s awareness of the different constancy functions that may be ascribed to an entity. Perception, in this sense, involves an ongoing process of monitoring the environment and of searching for specific bits of information, actively seeking stimulation that will answer prior questions directed towards the qualitative nature of entities present to the senses as toward the presence or absence of entities themselves.
Since, consciousness is dependent upon perception and the elements outside the individual stand as independent entities to the individual, it follows that even if one assesses one’s self before making judgments regarding the external world, one still holds an empirical stand on knowledge acquisition since the epistemological framework which one uses assumes the independence of the external world from the subject or perceiver.