1. Introduction
2. Two Competing Analyses
2.1. Conditional Perfection from the I-Principle
2.2. Conditional Perfection from the Q-Principle
2.3 Song's (2003) Analysis
3. Song's (2003) Problems and a Remedy
3.1 Song's (2003) Problems
3.2. Implicature Computation Based on the NoRedundancy Principle
3.3 A New Approach to Conditional Perfection
4. Concluding Remarks
References