With no emphasis on how to establish sets of moral principles and rules,meta-ethics seeks to analyze the moral concepts and moral judgments already made by normative ethics with conceptual,logical and linguistic analysis.

Based on the classification of meta-ethics; primary problems of the meta-ethics, the topic for the research is to discuss the dual ethical method of Stevenson's Emotivism, especially, its features and important roles in transition in west modern ethics.

As the founder of western modern meta-ethics,G.

What is more important is that, without theoretical concepts and frames provided by metaethics, we cannot explore some normative questions or issues with efficiency and depth.

And analytical philosophy reduced ethics to metaethics, which concentrated on logical and linguistic analysis of moral discourse but ignored the moral practice of the society.

Stevenson is a recognized leading representative of emotivism in metaethics, who have done great contribution to the development of metaethics.

Based on the moral dilemmas reasons,we distinguished these into three types: factual moral dilemmas,normative moral dilemmas and meta-ethics problems.

We,if analyzing the goodness and evilness of science and technology from view of meta-ethics,can get a deeper understand for ethics of science and technology,and form a new perspective of meta-ethics,which provides semantic guideline to exculpate the goodness and evilness of science and technology and help us achieve more effectively the goodness of science and technology.