Final answer:
Cosby suggests that play is a vital part of childhood and plays a central role in a child's development.
Step-by-step explanation:
When Cosby says, "The essence of childhood...is play," he means that play is a fundamental aspect of being a child. Play is crucial for a child's development, helping them learn important skills like problem-solving, imagination, and social interaction. It allows children to explore their world, experiment, and build their creativity. By emphasizing the importance of play, Cosby is highlighting its significance in shaping a child's overall growth and experiences.
Learn more about The significance of play in childhood