"原理的阐述" can be translated into English as "the elucidation of principles" or "the explanation of principles".
"Elucidation" implies a clear and detailed explanation or clarification, making it suitable for contexts where a thorough understanding of the principles is sought.
"Explanation" is a more general term, meaning the act of making something clear or understandable, and can also be used effectively in this context.
Both translations are accurate and can be chosen based on the specific context and tone desired.