Step 1: Understanding Roosevelt's views on fear.
In the lesson "Deep Water," Roosevelt recalls his childhood fear of water. He describes how he feared the water to such an extent that he would avoid it at all costs. He explains how this fear dominated his thoughts for a long time.
Step 2: Overcoming the fear.
Roosevelt explains that his fear was conquered when he learned to swim at a later stage of his life. He faced the fear head-on and eventually overcame it by getting into the water and gaining confidence through practice.
Step 3: The message.
Roosevelt conveys the message that fear is a natural feeling, but it can be overcome with persistence and the courage to face it. He encourages the reader to confront their fears rather than letting them control their life.
Final Answer: \[ \boxed{\text{Roosevelt said that fear is natural, but it can be overcome by confronting it with persistence and courage.}} \]