Behaviourist vs Scientist

One example that Mises liked to use in his class to demonstrate the difference between two fundamental ways of approaching human behaviour was in looking at Grand Central Station behaviour during rush hour. The "objective" or "truly scientific" behaviourist, he pointed out, would observe the empirical events: e.g., people rushing back and forth, aimlessly at certain predictable times of day. And that is all he would know. But the true student of human action would start from the fact that all human behaviour is purposive, and he would see the purpose is to get from home to the train to work in the morning, the opposite at night, etc. It is obvious which one would discover and know more about human behaviour, and therefore which one would be the genuine "scientist".