|Stimulus: is a change in the state of a variable which, by acting on a subject or ultimately a sense cell, can have or cannot have effect or a willingness to do so. Stimuli can occur both outside and inside a living system. While in an event that is without effect, one does not speak of a cause, one speaks very well of stimuli, which remain subliminally and thus trigger no reaction. The reason for this is that several levels are involved in the processing of stimuli and inhibitions may occur during processing.|
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Stimuli / narrow explanation: representations by stimuli: does not need truth conditions -
Existential quantification / Field: is only needed because we may not know exactly which class of stimuli is caused by the presence of rabbits.
Realism, Mathematics and Modality Oxford New York 1989
Truth and the Absence of Fact Oxford New York 2001
Science without numbers Princeton New Jersey 1980