The passage discusses two contrasting theories of development: continuous theories and discontinuous theories. The first main idea is that continuous theories of development propose that development occurs gradually, with skills developing smoothly as children are exposed to experiences provided by caregivers and the environment. These theories emphasize the significance of the environment rather than heredity in shaping a child’s development.

The second main idea revolves around the idea that discontinuous theories assume that children progress through predictable and unchanging stages of development. In these theories, it is believed that all children follow the same sequence in acquiring skills, although the rate of progress may vary from one child to another. Additionally, at each stage of development, children gain qualitatively different understandings, abilities, and beliefs. Although children may exhibit behaviors from multiple stages simultaneously, skipping stages is considered rare or nearly impossible.

The third main idea from the passage is that discontinuous theories of development focus on inborn factors as explanations for developmental changes over time, in contrast to continuous theories, which emphasize environmental influences. This suggests that discontinuous theories attribute the changes in a child’s development to innate factors rather than external experiences.

Finally, the fourth main idea is that discontinuous theories emphasize the idea that children pass through distinct stages of development, with each stage representing a qualitative shift in their cognitive and behavioral abilities. This stands in contrast to continuous theories, which emphasize a more gradual and smooth progression of skills.

In summary, the passage highlights the differences between continuous and discontinuous theories of development, with continuous theories emphasizing gradual development influenced by the environment and discontinuous theories focusing on distinct, inborn stages of development.