(Image from http://www.tpack.org/, updated 3/16/09)
Although many philosophers have typically defined knowledge as "justified true belief" and have spent decades, if not centuries attempting to understand each of these words, the definition of knowledge used here [by us] is more pragmatic and is influenced by scholars such as Dewey, Schon and Perkins (Dewey, 1934; Dewey & Bentley; 1949; Perkins, 1986; Schon, 1983, 1987; 1996). Perkins in particular poses a provocative metaphor: that of "knowledge as design" (Perkins, 1986). In fact he goes on to argue that knowledge can be considered a tool that is designed and adapted to a purpose. As he says:To think of knowledge as design is to think of it as an implement one constructs and wields rather than a given one discovers and beholds. The kinesthetic imagery implicit in knowledge as design fosters an active view of understanding worthy of emphasis in teaching and learning. (p. 132)In this view of knowledge, the truth-value of the knowledge is less important than what you can do with that knowledge—what has also been called usable knowledge (Kelly, 2003; Lagemann, 2002; National Research Council [NRC], 2002).