It is actually one of the most difficult of insights genuinely to reverse the direction of causality - especially for the first time (ie. doing it for yourself, rather than following in footsteps). But I can see that I have often made what I regard as my most-important 'breakthroughs' by reversing assumptions. For example, reversing the causal arrows of a relationship between entities or phenomena.
For instance, in medical science, maybe my best idea was related to 'depression' (i.e. severe endogenous/ psychotic depression, or melancholia) being a psychological response to immune-activating illnesses. This reverses the usual idea that depressed people have - as a consequence of their psychiatric condition - raised imnune markers, symptoms of malaise, pyrexia, increased rates of autoimmune and cardiovascular diseases etc. (This also meant that effective antidepressants worked by treating these physical causes and symptoms, rather than by treating the 'emotions'; again a reversal of causality.)
Reversing the direction of causality for depression and its treatment may seem simple, and it is simple once formulated; but it took me about fifteen years to sort-out and piece-together. Once the idea was formulated there was plenty of evidence to support it - but it was having the idea that was so difficult.
I came across a similar thing today in relistening to a lecture by William Arkle. It suddenly struck me with full force that I had taken Arkle's scheme of God's work and reversed the causality, in a way that might well confuse anyone following my frequent links to Arkle's work.
From Arkle I got the invaluable insight that God's purpose is to produce 'divine friends' - to raise his Sons and Daughters to (as near as possible) God's own level and to participate with God in the ongoing work of creation; but for these divine friends each to be a distinct person, an individual - so that each brings something new and original to the work (rather than merely repeating what God already brings to the business). This understanding I still hold-to.
But for Arkle, God's problem is how to make individuals from an original divine unity - from the singleness of one creator God. He suggests that this was achieved by God first dividing himself into male and female, then implanting a little flame of divinity into each person, then making a complex educational world unique for each person (i.e. unique from the specific perspective in which each specific person was 'placed' by God). In this varied reality, each person becomes unique by tackling the challenges and problems differently - thus Men grow-apart and become more and more different. So much for Arkle...
But underpinning my own Christianity is Mormon theology; which has men and women as distinct from the beginning, and each man and women an unique 'being' existing from eternity. (This also applies to God, who consists of two Heavenly Parents, a man and a woman).
From this combination between Mormonism and Arkle; I have developed my own understanding of God's problem which ends-up being almost the opposite of what Arkle said. I believe that God started-out with zillions of unique individuals (at odds with each other), living in a state of chaos - and God is aiming at a state where the 'divine friends' are able and desirous to cooperate harmoniously in the ongoing work of creating.
For me, now, this is the key to the specifically Christian concern with love; since it is by love that unique individuals are able-to choose-to cooperate in harmony (as we can imagine would happen in an ideal family).
It also clarifies the role of Jesus's work, which made it possible for any number of unique Men to choose (by following Jesus to resurrected eternal life in Heaven) to make a permanent commitment to loving creation. Each person is bringing his or her own unique perspective, abilities and motivations to the job - so that divine creation may continually expand in scope while remaining in harmony.
(My favoured analogy for Heaven is with an idealised wholly-loving extended family of immortals; continually being added-to by new and unique people - by descent, marriage, adoption, and true-friendship; but always - because of their mutual love - working together, and cohering in their work; because they each work for each other, as-well-as for themselves.)
Such a view is simple enough to explain (it didn't take me many words!) yet was probably impossible to formulate explicitly until the 19th century at earliest...
At least there seem to be no pluralist philosophies of this kind, until first Joseph Smith (the Mormon prophet) and later William James (the philosopher and psychologist) saw and embraced the possibility. This idea of metaphysical pluralism is, for me, one of the very greatest US contributions to the history of human development. Because, as far as I know, all previous philosophers/ theologians - since the ancient Greeks - seem to have assumed the primal unity of reality.
So here is another example of reversing causality - and an indication that it is a genuinely difficult thing to do!