A profound thinker like Calvin basically has to answer the following two questions: What “is” and what “ought” to be? The first question deals with what reality looks like, its ontological structure or one’s type of thought. The second question con- cerns one’s view of the norms valid for created reality, the direction which one’s life takes or the spiritual trend of one’s thinking. In a previous article in the same issue of this journal, Calvin’s answer to the second question was already investigated. Among all the spiritual trends of his time, his main motive was to be obedient to God, his Word and his will. We now turn to the answer to the first question: What types of philosophies and theologies emerged within these various spiritual trends which could have influenced Calvin’s thinking? The investigation develops through the following steps. Firstly, the question is posed whether Calvin really succeeded in the direction of his thinking, viz. to be a radical-biblical reformational thinker. This question is divided into three sub-questions: was Calvin influenced by extra-biblical ideas? If so, to what extent? How did he employ pre-Christian insights? The second and main section tries to answer these difficult questions by reviewing seven most prominent philosophical and theological types of thinking. The third section indicates the contribution of a Christian philosophical analysis of his worldview. The con-cluding section draws the last lines of Calvin’s “intellectual portrait”.