TIM,
I do agree that ion some part mental anguish can be caused by excessive thinking. I also know from experience that as physical objects our brain functions (electrical impulses, chemical interactions) are affected by environmental factors. No amount of rational thought can overcome sever food deprivation, for instance. The mind will lose the ability to ration without rations.
An attachment to false ideals is problematic from many standpoints. In education, politics, religion, etc. Anytime an imaginary concept is revered more than reality dissonance will ensue. This is not to say we should not conceptualize anything. By having an ideal of fear or an ideal of hope we are motivated to hide or fight.
I disagree that animals cannot make cognitive comparrisons. Whatever internal mental faculties animals conduct are generally undectectable by humans (some claim to know the thoughts of critters, but most don't). Just because we cannot detect something does not negate its import-its "realness". We cannot see cosmic radiation, but some of our creations (technologies) can. Perhaps we will find one day that those who anthropomorphized animals, were indeed correct. Perhaps animals do think of themselves in comparisson to others. I have seen animals cooperate based on differening talents and find it hard to think they are unaware of their differences.
From personal experience I know that a person can outreason anguish. The ability to self-soothe is a hallmark of a healthy individual. We can "talk ourselves down." I disagree with Hume.
You noted that action is based on a maximization of benefits. Does not the act of reasoning lead one to choose from among percieved benefits? One must make value judgments and predict outcomes in order to say "this will benefit me more than that".
I disagree with any philosophy that dictates only one causality for all else. To say that pleasure alone drives us is in some respects true. But the source of that pleasure can be pain. Self-harm and deprivation illlicits a "feel-good" responce in some individuals, so through hedonistic desire they cut or starve themselves. Altruism is the ultimate "feel good", achieved by putting oneself in jeopardy for the benefit of another. Pleasure from pain.
Desire may drive action, but reason can create desire where none existed before. Desire does indeed cause angst. The very definition of desire is for something you do not have. You do not desire what you have. Semantics....
There are indeed many "opiates." Some with more detrimental side effects than others. The denial of all desire could lead to what many would consider negative effects.
I am a believer in totality. Rational and Irrational. Hell, I even marginally believe in that which I do not believe entirely.
Moss