Knowledge is

no doubt

an important wealth to the mankind but there has not a knowledge theory existed yet till the present time.An attempt was made in[1]to establish a foundation of knowledge theory that includes a series of basic issues such as the related concepts and definitions

the methods of representation

the measurements

the reasoning and decision rules.Here in the paper the nucleus of knowledge theory

the mechanism of knowledge creation and that of intelligence production

will be presented.It is believed that the establishment of the knowledge theory will lay a solid foundation to the unified theory of information

knowledge

and intelligence and that will greatly faciliate the effective utilization of information and knowledge leading to better advancement of the research in the field of intelligent machines.