This paper, firstly，shows that both rationalism of Descartes and empirical scepticism of Hume can not rule out the belief in science by means of analyzing the process of scientific research .There are kinds of beliefs that are common sense，scientific sense and worldview in science.They play different roles respectively in the development of science from the empirical to the theoretical, and again to the highly theorized. Secondly，it discusses the ways of formation and function of belief in science by the analyses of the formation and function of paradigms of science, the assessment of scientific theories and the impact of society on science.Finally，it elaborates that the belief in science intrinsically relates to the scientific research，that the program of universal scepticism can only lead to nihilism in the end，and that the development of science is in the process of dialectical movement for belief and scepticism..

This paper analyzes the current status of garbage pollution，the composition，production and their changes in our country，and particularly indicates that the previous treatments have not met the present demand.From the view of the sustainable development，the paper points out some measures and suggestion on the future garbage disposal.