Perhaps the difference between the progress hard sciences (engineering, physics) made, as opposed to the "soft" sciences (e.g., psychology, sociology) could partially be attributed to what's at stake when the predictive power of the Soft Sciences increases--reaches near-perfection. In explaining the physical world, humanity enjoys the benefits of being able to predict weather patterns, the trajectory of falling rocks, the conduction of electricity. There isn't a great contract between those who know the answers to these questions, and those who don't.  However, if human behavior can be predicted; if it can be fully understood-- what will be the consequences; the toll society (or those not privy to this information) will pay? Indeed, what price do we pay now for the partial understanding the soft sciences enjoy? Perhaps to some extent the practitioners of the soft sciences--consciously or subconsciously--understand this end result of absolute knowledge. When this field as a whole stands at the brink of full understanding, it will be the this worrisome question, that will keep this Science soft.