Final answer:
The main idea in the ninth amendment is that some rights are not included in the constitution but are still protected.
Step-by-step explanation:
The main idea in the ninth amendment is that some rights are not included in the constitution but are still protected. The ninth amendment states that just because a specific right might not have been explicitly listed, it doesn't permit the government to take it away. This amendment, along with other amendments, has worked to further protections of privacy for citizens.