The narrowness of acquired ability

Earlier theories of the mind - like the formal discipline theory - assumed that things like reason, language and attention were like muscles and that any activity strengthened them. It led to views that learning Latin and geometry was essential even though few students would use these skills.

Edward Thorndike disproved this theory in 1901. He formed a new theory known as the identical elements theory, which suggested that two problems must share common elements for one skill to apply to another.