Haptic perception by metabolic, toxic and/or immunologic factors. Examples of medical conditions that can cause neuropathies are diabetes mellitus, chronic kidney disease, thyroid dysfunction (hyper- and hypothyroidism) as well as hepatitis, liver cirrhosis and alcohol dependency. Loss of the sense of touch is a catastrophic deficit that can impair walking and other skilled actions such as holding objects or using tools. Immersive environments can recreate the feeling of haptic interaction. Exoskeletal gloves such as the Exo-Skin Soft Haptic exoskeletal interface, developed at Drexel University, can be programmed to take a patient through a program of physical therapy exercises to retrain muscles and
Analogy of the sun region in which truth and real being brightly shine, it understands and knows it and appears to have reason; but when it has nothing to rest on but that which is mingled with darkness—that which becomes and perishes, it opines, it grows dim-sighted, changing opinions up and down, and is like something without reason. ('The Republic, VI: 508d; trans. W. H. D. Rouse) The allusion to "...that which becomes and perishes..." relates to all of that which is perceived by the bodily senses. The bodily senses make it clear that all visible things are subject to change, which Socrates categorizes