*IDEALISM*

Here, "Idealism" doesn't mean what it means in present-day ordinary English, as "hoping for the best." "Idealism" here means a kind of philosophy that preaches "mind over matter," and that the world (or whatever we can perceive of it) is nothing but a creation of our own minds.  This is the kind of philosophy that says "My world is what I think," or "My thoughts and feelings determine what is real to me," or "What's true for you may not be true for me, and vice-versa."

Certain religious traditions also promote this sort of belief.  Some teach that alleviating human pain, suffering and injustice doesn't matter nearly as much as doing rituals, thinking about the after-life, reciting prayers or "saving my own soul." Others say that poverty, illness, exploitation and death are nothing but illusions, or are punishment for what you did in past lives, or justified vengeance for a crime of our long-ago primeval ancestors, or are retribution for errors in your present life. So, these human tragedies don't really matter, or simply can't be helped.

Another kind of "idealism" is to believe that feelings, desire, love, spontaneity or "fun" are "everything," and material conditions or political and economic struggles somehow don't really matter.  Even feeling in your guts that "this world sucks," but not doing anything about it except complaining, is a form of idealism.