A common view of science is that scientific knowledge is simply derived from the facts. In the first part of the book this view has been criticized because much of this statement cannot be justified, in this chapter it will be described why this view is not completely incorrect. It is claimed that science is based on facts and that these can be collected with the use of the senses. It is about what we can perceive with our senses instead of personal opinions. If the observation is done careful and unprejudiced, the facts will be a secure objective basis for science.In the seventeenth century, modern science became possible. Until that time, the knowledge was based on authority of Aristotle and the Bible. Two schools of thoughts formally state this common view. Empiricism claims that scientific knowledge is based on sense perception. Positivism communicates the same in a broader sense still and was less psychological orientated. The logical positivists build further on the idea of positivism and paid more attention to the logical form of the relationship between scientific knowledge and facts. There are two issues involved in the statement that science is derived from facts. The first is the nature of the facts and how scientists can have access to them, the second is how laws and theories are derived from facts once they have been obtained. The assumed basis of science can be summarized within three statements. Firstly, observers perceive the world via their senses in an unprejudiced fashion. Secondly, the observed exists independent of any theory. And thirdly, the observed is handled as facts that serve as a...