Skinner interview with Even Segal

Watch the following videos and answer the question/s below:
Skinner interview with Even Segal (total 64 minutes)
Part 1: https://www.youtube.com/watch?v=xjiXX418MMk&list=PL51478B7DFF4F8537
Part 2:https://www.youtube.com/watch?v=JihNtwtbApI&list=PL51478B7DFF4F8537&index=2
Part 3:https://www.youtube.com/watch?v=MZW_mff4RV0&list=PL51478B7DFF4F8537&index=3
Part 4:https://www.youtube.com/watch?v=q6CnHk7dyUs&list=PL51478B7DFF4F8537&index=4
Part 5:https://www.youtube.com/watch?v=ZXqRRzg1J_s&list=PL51478B7DFF4F8537&index=5
Part 6:https://www.youtube.com/watch?v=3gKNBPv-p5M&list=PL51478B7DFF4F8537&index=6

1. How does Skinner talk about covert behaviors (private events) in terms of thoughts/thinking? (expected length 1 page)