[myco_logic]

Just as having an in depth understanding of mathematics, physics, or engineering helps us to make more informed decisions, so too do the humanities. Fields of study such as philosophy, sociology, or aesthetics do not attempt to establish, as you put it, subjective unverifiable "truths" (to do so would be quite infeasible in the first place). Instead they allow for discussion and aggregation of information and reasoned opinions, so that a comprehensive understanding of the field and its many schools of thought may be reached.

Coming back to the wind farm, even once we have the objective variables, the decision we make will be based on factors of morality, geography, aesthetics, sociology and politics. By having a broad understanding of these fields and the various paradigms contained within them, we can produce a more informed decision than if these aspect were ignored completely.