First, regarding the left hemisphere:
From everything we know about the hemispheres, we would expect that, in the left hemisphere’s world, truth would be conceived as a thing, rather than a process. Truth, this thing, would be conceived of as existing in the realm of subjectivity (in the mind) as a suitable representation of something conceived of as existing in a realm of objectivity (outside the mind). From this point of view the way to approach truth would be to start with a secure set of facts, and then work upwards by rules of logic, to a series of other facts, putting one secured item on top of another, to build the pyramid of (represented) truth.The Matter with Things, 382
Regarding the right:
So how would the right hemisphere conceive truth? Rather than conceiving it as a thing, it would experience it as a process, one that, in this case–not just for now, but in principle–has no ending. More importantly, it would see that truth is a relationship. Instead of seeing a subjective realm and an objective realm which should as near as possible mirror one another, it would see a constant reverberation between two (never completely distinct) elements within our consciousness–thoughts and experiences–whereby they ‘answered‘, or co-responded to, one another; this even better accord, or attunement, would be the evolving truth. It would be intrinsically incomplete, but constantly in the process of completing itself; and uncertain, though constantly approaching nearer to certainty; incapable of being grasped except through embodied being, through a consciousness that is in the fleshed and engaged in the world. We would find out what was true only by testing it on the pulse of experience–whether it corresponded with the totality of our experience, not just with one (cognitive) part of it. Because of this it would be unique and necessarily many-stranded.The Matter with Things, 384
What might be the implications of McGilchrist’s thinking about modern theology, and especially regarding notions of the Trinity?