Logic and information

A computer virus is merely a small piece of program in nature, and similar to that of a computer virus, an organism may be considered as an information system in nature. This paper analyzes above idea from different ways. 1) DNA sequence satisfies the basic requirements of an information system; 2) The controls of a man and a robot both obey the principle of cybernetics; 3) How a man can have ideas but a robot has no such capacity; 4) The advantages of understanding a living organism from the point of view of information systems.