If your message is specific, definite, and vivid, then you are applying the principle of clarity in communication. Clarity is one of the key principles of effective communication, and it involves being clear and concise in your message. A specific, definite, and vivid message is one that is easy to understand and is more likely to be remembered by the recipient. By applying the principle of clarity, you can ensure that your message is communicated effectively and that the recipient understands the intended meaning.