Final answer:
Organic shapes are difficult to define due to their complexity and fluidity, resembling elements found in nature that lack uniform edges. Their ambiguity is influenced by variations in form, making it challenging to describe and categorize them precisely.
Step-by-step explanation:
Organic shapes are hard to define due to their complex and irregular forms which often lack uniformity and precise edges. Unlike geometric shapes that have exact measurements and angles, organic shapes are more free-form and fluid, often resembling elements found in nature. This ambiguity in form makes it challenging to describe and categorize them in a precise way.
In artistic compositions, identifying positive and negative shapes can become complex when shapes are implied by surrounding elements, rather than being explicitly outlined. Furthermore, when analyzing the form and structure of organic shapes, variations in size, shape, and composition reinforce their complexity, which is often intensified by dynamic changes during an organism's existence or by the diverse ways in which shapes can interrelate within an artwork.
The distinctions between organic lines, such as those in Albrecht Dürer's prints, and geometric lines also exemplify this complexity. Inorganic lines tend to be straight or uniformly curved, while organic lines are more unpredictable, which adds to the difficulty in defining organic shapes.