Short Answer 
The riddle explores water’s transparency, allowing clarity while being invisible, and its ability to manipulate perception through depth, creating illusions. It emphasizes water’s dual nature: essential for life yet capable of danger, symbolizing memories that are both ever-present and evocative of the past.
Step 1: Understanding Transparency
The first line of the riddle highlights that water is invisible yet allows for clarity. Water is often seen as a transparent medium, making it easy for us to look through it. This property means that while we cannot see the water itself, it enhances our ability to see what lies beneath its surface, demonstrating its essential role in viewing our surroundings.
Step 2: Recognizing Depth and Illusion
The second line describes how water can be both shallow or deep, influencing our perception. Shallow water may not obscure much, but deep waters can create an illusion, making objects appear closer due to magnification. This unique characteristic allows distant items to seem more accessible, playing with our sense of distance.
Step 3: Reflecting Life’s Duality
The riddle’s last clues address water’s importance and its dual nature. On one hand, water is crucial for survival; without it, we can face dire consequences (“stumble”). Conversely, excessive water, as seen during storms, can lead to danger and loss of visibility (“blind”). Additionally, water stands as a metaphor for memories, always present in our lives, yet can also evoke past experiences, making it both a constant companion and a reflective element.