There is no internal theory, only internal theory and external theory.

Internalization theory: Vygotsky, Leontief, Gary Peilin.

1, Vygotsky of the Soviet Union once put forward the hypothesis that advanced psychological functions such as internal intelligence processes originated from external activities.

2. Leontief believes that external material activities and internal spiritual activities are the same structure, so the two activities can be transformed and transformed.

3. Gary Peilin put forward five stages of transforming external material activities into intellectual activities on the basis of experiments: the orientation stage of activities; Stage of material or materialized activities; The external speech activity stage of vocalization; Silent external speech stage; Internal speech activity stage.

Xunzi, Locke and Skinner.

1, Xunzi: We should reform the human factor.

2. Locke: The mind is like a whiteboard. It has no content and anyone can discredit it. External forces determine human development.

3. Skinner: Human behavior and even complex personality can be shaped, changed, controlled or corrected by external reinforcement or punishment.