The difference between pleasure and hope is striking - it is quite usual to experience one without the other.
At the extremes, presumably (to all appearances) a intravenous heroin junkie, or a cocaine crack-head, experiences extreme pleasure - probably more extreme than any natural pleasure. Yet such people seem utterly despairing - that is what appears from their behaviour, or is empathically perceived.
By contrast, someone is extreme pain, and misery of circumstances, or suffering from bereavement; may be extremely hope-full.
As Thoreau memorably phrased it, the mass of men may lead 'lives of quiet desperation' (hope-less-ness) - yet will nonetheless often self-report considerable happiness.
The best psychological conceptualization of pleasure is that it is the brain's representation of a body state - so if the body state is manipulated in certain respects by a drug such as heroin or cocaine, then the brain perceives this as pleasure. So, it is almost a 'mechanical' thing.
The imagination is another kind of thing. It presumably requires a certain physical basis - brain and nerves, for example - but it does not have any specific location, and has a high degree of autonomy; it is not just an average of emotional states or a product of circumstances.
So people in the most physically-favourable of circumstances, in perfect health - including mental health - may feel utterly hopeless, may be in a state of despair. So, what and where is it that hope operates?
Hope or despair seem to be rooted in our basic ideas - what could be termed metaphysical ideas: that is, our assumptions of beliefs regarding the fundamental structure of our lives and the world, and how the two fit together.
That 'place' of hope, or despair, is the imagination - and there is an objectivity of the imagination. I mean, the imagination cannot be fooled, the imagination cannot be hopeful on the basis of simply wanting hope.
If we feel despair because of our fundamental metaphysical assumptions concerning the basic nature of life and reality, then we cannot simply get rid of this despair with hope by arbitrary self-assertion.
Not everything 'works' in generating hope or alleviating despair: only some things are effective.
It is as if hope or despair is the causal end-product or consequence of our imaginative grasp of reality - hope flows from fundamental beliefs and assumptions.
But can these fundamental beliefs or assumptions be changed? Yes, of course: that is the experience of 'conversion'. But what we convert-to is not arbitrary - in a sense we can only convert-to that which gives us hope; and if our metaphysics leads to despair, then it is very difficult to believe it, because the capacity for any kind of belief tends to be eroded by despair.
I tend to the view that we almost-must believe that which gives hope - and probably should-not believe that which leads to despair. At least, the direction which our metaphysics should develop in - because, of course, the same basic metaphysical belief may lead first to hope, and then - with time, experience, new circumstances - this hope turns to despair.
In such a fashion our imagination is an inner guidance system; properly monitored it points us in the direction we 'ought' to go - but this direction may not be (probably will not be) the direction we will continue forever.
What I am, of course, saying - is that the imagination is divine; because if it were not divine it would not have ultimate validity. Imagination is a faculty which is a gift of God.
And there is a tremendous difference between being guided by the imagination - which is being guided by hope-despair (moving towards and believing that which generates hope, away from and avoiding that which leads to despair), and on the other hand being guided by pleasure-pain.
My impression is that apostasy (lapsing from a religion) often comes from being guided by pleasure-pain - so a hope-full religion is abandoned, because abandoning it leads to more pleasure or less suffering (especially more sexual pleasure, or less sexual frustration - in such ways the sexual revolution has been the most destructive wrecking ball of religion over the past century).
But if the religion is itself leading to despair (rather than pain, suffering or misery) then that probably is a very good and valid reason for abandoning it - and seeking some modification of that religion, or some other religion.
And conversely, the spiritual seeker probably ought to be making choices based upon that which leads to hope - and try to avoid being misled by the lures of happiness, pleasure, fun and excitement.
Maybe this sounds to you like relativism? But if the imagination is divine, then what I propose is objectivity: in seeking hope, it will lead us to the truth.
Ideally, and properly, our religion ought to be that which fills us with strong and robust hope, and leads on from hope to more hope. This is a function of the imagination - and one of the most vital reasons Man has been given this faculty.