About Deaf-Blindness > What is Deaf-Blindness. Deaf-blindness is a low incidence disability and within this very small group of children there is great variability. Many children who are deaf-blind have some usable vision and/or hearing. The majority of children who are deaf-blind also have additional physical, medical and/or cognitive problems.
Introduction-David Hume. The Philosopher David Hume is famous for making us realize that until we know the Necessary Connection / cause of things then all human knowledge is uncertain, merely a habit of thinking based upon repeated observation (induction), and which depends upon the future being like the past.
Rational choice theory assumes that all people try to actively maximize their advantage in any situation and therefore consistently try to minimize their losses. The theory is based on the idea that all humans base their decisions on rational calculations, act with rationality when choosing, and aim to increase either pleasure or profit. Rational choice theory also stipulates that all complex social phenomena are driven by individual human actions.