B.J. Fogg in his book Persuasive technology brings rhetorics to computer science. he suggests the term captology as the study of technologies that persuade people. Persuasion can be achieved by changing behaviors and attitudes of the user. to achieve this he offers a functioinal triad; computers as tools, as media, and as social actors. in each classification computers have the capability to persuade people to change. the critical point at this point is the ethics, and credibility of the computers. for a perception of credibility, computers should possess trustworthiness and expertise on that topic. the picture shows an example of computers as media. this is a ‘baby think it over’ baby simulator that gives vicarious experience for teenagers. the goal is convincing teenagers about the early parenting issue.