Tropes are the figures of rhetoric that create imagery. A rhetorical image is a double picture generated by linguistic means and based on the co-presence of two thoughts of
different things active together – in I.A.Richards terminology, on the co-presence of a “tenor” and a “vehicle”. The tenor is the subject of thought in a trope; the vehicle is the concept of a thing, person or an abstract concept with which the tenor is compared or identified.
The image, i.e the tenor-vehicle relationship, can be described from more than one viewpoint, it has several aspects.
Psychologically, images are based on association, or the mental process of establishing connections between ideas, feelings, sensations, etc.
*NOTE Psychology is the study or science of the mind and the way it works and influences behavior.
From the point of view of logic images are based on analogy, or a form of reasoning in which one thing is inferred to be similar to another thing in a certain respect, both things being different on the whole. The connection, the similar feature is known as tertiumcomparationis or the ground.
*NOTE Logic is the science or study of careful reasoning by formal methods.
Linguistically, a trope is an opposition set up between the deviant segment and the paradigm of elements that would be normal in the given context, i.e. it is an interaction between usual and unusual collocations.