Final answer:
The answer to the riddle is your shadow, which cannot be touched or caught. Shadows mimic the movements of their source object but lack physical substance, making them intangible yet ever-present followings. Understanding shadows is part of learning the physics of light and our interactions with it.
Step-by-step explanation:
The answer to the riddle, 'What follows you and copies your every move, but you can't touch it or catch it?' is your shadow. A shadow occurs when an object blocks light, causing a silhouette to form on the opposite side from the light source. It's an intangible, dark reflection of oneself or another object. Shadows cannot be touched or held as they lack physical substance, though they mimic the movements of their source object closely.
The nature of shadows is such that they can appear to be almost mystical, following us eerily, similar to the literary references provided. Thinking you have captured it or understood it completely can be misleading, much like trying to chase a dream or a deer in the enchanted forest that is always just out of reach. This aligns with the quotes where the pursuit of a thing - be it beauty, a dream, or the concept of a shadow - is likened to an elusive chase.
Understanding the physics behind shadows can be captivating, much like playing a game of catch with the laws of gravity, where objects thrown upward follow an arc. Shadows too move and stretch in ways dictated by the movement of the light source and the object casting the shadow. Understanding the science behind our everyday observations help in demystifying such simple yet profound phenomena as shadows.