Which of the following statements is/are correct?

I. Negative analytical propositions are contradictory

II. Negative synthetic propositions are not self-contradictory

Three Divisions of Knowledge: Based on the way and manner in which it is obtained, knowledge can be classified under three heads:

• A Priori Knowledge: A priori knowledge is a knowledge whose truth or falsity can be decided before or without recourse to experience (a priori means ‘before’). The knowledge that is prior has universal validity and is once recognized as true. The propositions that come under this category of knowledge are known as analytical propositions. For example, bachelors are unmarried men. Its negative is self-contradictory (bachelors are not unmarried men).
• A Posteriori Knowledge: A posteriori knowledge is knowledge-based upon observation and experience. This is the knowledge of the scientific method stressing accurate observation and exact descriptions. These propositions give us factual information whose truth or falsity can be decided only through observation and verification. These are called synthetic propositions. One can negate the proposition "Snow is white" - assuming that whiteness is not a defining characteristic of snow - we get "snow is not white", which though false, is not self-contradictory.

​Thus it is clear that both I and II is true.