Sentence:  If it could be shown that judgments of good and bad were not judgments at all , that they asserted nothing true or false , but merely expressed emotions like `` Hurrah '' or `` Fiddlesticks '' , then these wayward judgments would cease from troubling and weary <WSD>heads</WSD> could be at rest . 
Meaning of the word marked with <WSD> tags:  that which is responsible for one's thoughts and feelings; the seat of the faculty of reason