When John B Watson made the statement that if he had a dozen infants he could take any one of them at random and train him to be a doctor merchant thief etc he was referring to the powerful effect?

John B. Watson's statement emphasizes the powerful effect of environmental factors on human behavior and development. He believed that through conditioned responses and behavioral training, any child could be shaped into a specific profession or personality, regardless of their innate traits or background. This idea underscores the principles of behaviorism, which focus on observable behaviors and the impact of external stimuli rather than genetics or internal thoughts. Watson's assertion reflects the belief in the malleability of human nature through systematic training and conditioning.