Abstract

According to a common view, conscious thoughts necessarily involve quasi-perceptual experiences, or mental images. This is alleged to be the case not only when one entertains conscious thoughts about perceptible things, but also when one thinks about more abstract things. In the case of conscious abstract propositional thoughts, the idea is that they occur in inner speech, which is taken to involve imagery (typically auditory) of words in a natural language. I argue that unsymbolized thinking and total aphantasia cast doubt on this common view. Unsymbolized thinking is the experience of thoughts that does not involve imagery. Total aphantasia is the inability to produce mental images of all sensory modalities. I consider and reject the objection that these individuals are mistaken either because their thoughts do involve images, or because those thoughts are not conscious. Thus, unsymbolized thinking and aphantasia provide evidence that conscious thoughts can occur without imagery.