I'm still struggling with the difference between rationalism and religion. Both doctrines use something we call 'metaphysics' and there's been a constant struggle between the two sides to claim particular words and concepts. The history of human development has been a constant bickering over how we understand reality.
The problem is, that there is metaphysics; and then there is metaphysics. It seems to me that the term is used indiscriminately to apply to two areas of thought which should be absolutely separate . It would be best to call one logic, and the other spirituality. It is unfortunate that the term applies as valid to the two equally. The difficulty is compounded by the fact that concepts generated within the one discipline can almost always be translated into the other with very little difficulty, although their implication is far from identical.
Terms like 'eternal', 'spirit', 'absolute' find use in both - and when a clearer definition is sought to clarify the nature of these concepts, we find ourselves still at a loss to understand of which area the speaker is referring. The idea of a non-physical entity - any non-physical entity - leads us into the same trap. Is the 'soul' an independent, real thing - or is it a word we use to refer to a quality we experience of someone? The word is still in common parlance as a metaphor. But what is the actual referent?
It has been argued that the majority of philosophers have in fact been talking of the 'realm' of logic: Plato, Aristotle, Hegel, Leibniz, Wittgenstein...all were talking of no 'religious' qualities: they sought merely to describe the difference between the material world outside of us, and the world of thought inside of us. The problem comes when philosophy and religion meet, and thinkers such as Maimonides attempt to explain religious concepts by means of philosophical concepts, and thus identify the two. Now, this blurs the line and we know longer know whether in fact there is a real difference between the religious God and the Absolute of the philosophers (although the distinction between the concepts should be intuitively clear to us); between the Soul of religion, and the Spirit of philosophy (or even the simple idea of a person's 'essence'); or between the angels and the metaphorical message-bearing elements of manifestation attested by Maimonides.
Are these concepts identical? Kierkegaard definitely didn't think so. An autonomous non-physical reality has no place in philosophy, but it is the essence of religious metaphysics, which postulates beings and actions which are real in precisely the way we are, while having no material presence. But where does the use of metaphor begin and end? Do the intelligent, the rational of today, understand the power of myth as metaphor for the logical concepts of philosophy and all the soft mind-based experiences of meaning? Was anything else ever meant by these words? Many still believe in the literal truth of angels, a personal God, and the afterlife. Are these people merely fools, those who cannot exercise logic enough to grasp the concepts behind the terms and so naively create a supraphysical realm which is clearly not 'there'? Of the Abrahamic faiths, no scripture talks of ought but this world we inhabit. The metaphysical interpretation has always come after, 'on top' of what is talked of in the holy books.
My problem is this: Surely one must be correct. If we explain away the difference by saying that one is metaphor for the other (as Hegel did, and Averroes and Maimonides before him), then that still leaves us with a literally corect understanding and a literally false one. If religion is a mythical, 'dreamlike' description of philosophical truths, then philosophical logic must take a higher place than religious revelation.
And in doing this, we strip God of any personhood whatsoever: by rejecting the anthropomorphic imagery in favour of a logical Absolute, we are effectively destroying the fundamental humanness offered by religion - and this is what so often has caused the downfall of rationalism, whether in Islam, Judaism, Christianity, or even Hinduism.
But truth must lie somewhere. Is it again too much of an anthropomorphism to demand that the universe has a conceivable structure that is graspable by humans? Or is it precisely this element of mystery, that mere mortals cannot perceive the whole of reality except from within our limited subjective experience of it, is it precisely this fact that makes being alive so unpredictably special?