A late bloomer is a person whose talents or capabilities are not visible to others until later than usual. The term is used metaphorically to describe a child or adolescent who develops slower than others in their age group, but eventually catches up and in some cases overtakes their peers, or an adult whose talent or genius in a particular field only appears later in life than is normal – in some cases only in old age. Children There are many theories of the way in which children develop, proposed by authorities such as Urie Bronfenbrenner, Jerome Bruner, Erik Erikson, Jerome Kagan, Lawrence Kohlberg, Jean Piaget, and Lev Vygotsky. Although they disagree about how stages of development should be defined, and about the primary influences on development, they agree that a child's development can be measured as a predictable series of advances in physical, intellectual and social skills which almost always occur in the same sequence, although the rate may vary from one child to another. When a child falls behind their peers at some stage of development, their teacher may perceive that the child is "backward". There is strong evidence that this perception may become self-fulfilling: although the child catches up, the teacher may continue to rate their performance poorly, imposing a long-term handicap. Thomas Edison's mind often wandered and his teacher was overheard calling him "addled." This ended Edison's three months of official schooling. His mother then home schooled him. Edison may have had some form of Attention-deficit hyperactivity disorder (ADHD), which the American Psychiatric Institute says affects about 3 – 5% of children. A notable example of a child who overcame early developmental problems is Albert Einstein, who suffered from speech difficulties as a young child. Other late-talking children who became highly-successful engineers, mathematicians, and scientists include the physicists Richard Feynman and Edward Teller. Neuroscientist Steven Pinker postulates that a certain form of language delay may in fact be associated with exceptional and innate-analytical prowess in some individuals. Dyslexia is a learning disability that may affect 3–10% of children. It is thought to be the result of a genetically inherited neurological difference from "normal" children, and has been diagnosed in people of all levels of intelligence. Studies indicate that 20% to 35% of U.S. and British entrepreneurs have the condition: by definition, late bloomers. Researchers theorise that dyslexic entrepreneurs may attain success by delegating responsibilities and excelling