In a sense, we might say that they experience an enhanced form of conscious experience as opposed to the typical disorder, that is, something is added to conscious experience instead of the more typical subtraction.ģ. Still, what “it is like” to be a synesthete must be quite different than most of our “normal” conscious experience. Synesthesia can, for example, aid one’s memory of names and phone numbers and be an asset for creative art. In fact, the vast majority of synesthetes prefer to have synesthesia and could not imagine life without it (though there are some exceptions as we will see later). Unlike many other abnormal psychological phenomena, however, synesthesia is not a disease or illness and is typically not harmful. This is presumably because these synesthetes not only see but also hear the patterns. These synesthetes outperformed control subjects on a difficult visual task involving rhythmic temporal patterns, for example, judging whether two successive sequences (either both auditory or both visual) were the same or different. Saenz and Koch report evidence that, for at least four synesthetes, seeing visual motion or non-moving visual flashes automatically causes the experience of sound ( 5). Motion-sound synesthesia involves hearing sounds in response to visual motion and flickers. Finally, I shed light on why synesthesia is virtually always one-directional and its relation to some psychopathologies such as autism. I also explore the possibility that many forms of synesthesia can be understood as experiencing what I will call “second-order secondary properties,” that is, experiences of properties or qualities of objects induced by the secondary qualities of those objects. After making some preliminary distinctions, I first engage critically with Sollberger’s view that there is reason to think that at least some synesthetic experiences can be viewed as veridical perceptions, and not as illusions or hallucinations ( 4). For example, some synesthetes experience a color when they hear a sound, although many instances of synesthesia also occur entirely within the visual sense. Synesthesia is the “union of the senses” whereby two or more of the five senses that are normally experienced separately are involuntarily and automatically joined together in experience ( 1, 2, 3). In doing so, I shed some light on why synesthesia is typically one-directional and its relation to some psychopathologies such as autism. Among other things, I explore the possibility that many forms of synesthesia can be understood as experiencing what I will call “second-order secondary properties,” that is, experiences of properties of objects induced by the secondary qualities of those objects. In this paper, I first mainly engage critically with Sollberger’s view that there is reason to think that at least some synesthetic experiences can be viewed as truly veridical perceptions, and not as illusions or hallucinations ( 4). Synesthesia literally means a “union of the senses” whereby two or more of the five senses that are normally experienced separately are involuntarily and automatically joined together in experience ( 1, 2, 3).