the wigwam man

“But moral associations which are wholly of artificial creation, when intellectual culture goes on, yield by degrees to the dissolving force of analysis; and if the feeling of duty, when associated with utility, would appear equally arbitrary ; if there were no leading department of our nature, no powerful class of sentiments, with which that association would harmonize, which would make us feel it congenial, and incline us not only to foster it in others (for which we have abundant interested motives), but also to cherish it in ourselves; if there were not, in short, a natural basis of sentiment for utilitarian morality, it might well happen that this association also, even after it had been implanted by education, might be analyzed away.” (Mill 265)

I am not sure that moral association can ever transcend artificial creation. Furthermore, it has been one of the fundamental problems in all of philosophy that every way we think can be analyzed away because of this artificiality of our thoughts. Even something as definite as mathematics can be analyzed to be worth nothing if you make it so, such as if you were about to be eaten by a shark because you were preoccupied with solving some math problem. So what does this mean? Should I not trust what I think because it is artificial in nature? In terms of utilitarianism, how can I dignify this way of thinking as the holy grail of belief after considering a statement like this?
Words are our connection to meaning and purpose within the universe. Simultaneously, words are a fabrication of man. Ideas, which are the combination of words, such as utilitarianism, can be positive in nature; however I am not sure that they can ever be substantiated to be any closer in correlation with our purpose then say egotism is. The problem seems to be that it is impossible to conclusively prove that purpose exists at this time. It all seems to be a fabrication of our imagination. Is it all just a trick of the mind?