Abstract: The teleological model opposed by Bloor's "Strong Programme" is derived from the teleological approach proposed by Barry Barnes,they all deny that the development of science can be seen as an evolutionary process of truth. They believe that scientific knowledge is a belief that should be included in the study of knowledge sociology. Bloor further proposed a causal model that is opposite to the teleological model and constructed four "Strong Programme" that Sociology of Scientific Knowledge should follow. He strives to make Sociology of Scientific Knowledge a universal discipline. Bloor claims that the causal model and the teleological model are two mutually exclusive metaphysical views,but in fact,the causal model is not opposed to the teleological model,and they actually have similarities. Meanwhile,he also has many problems in the demonstration and defense of the causal model. This is an incomplete "Strong Programme".