you're confusing "is" with "ought."

the fact that people act like this and there's a 50% divorce rate would indicate that we're not going about things as well as we could.

if a social scientist were to say that this is what we "ought" to do, then he would be a social philosopher. he can introduce new variables and test them, but as soon as he brings in the "ah yes, this is the best one!" he is no longer a dispassionate scientist.