Current cosmology: focused on information, holographic principle and black hole event horizons. Lots of conjecture but not as much empirical evidence in favour of one over the other. Importance of mathematics cannot be overestimated in current physics, but seems very easy to mistake the mathematical formulas describing phenomena for the phenomena itself. See Bertrand Russell on the mathematical skeleton of reality.
Idealism: in its classical form a powerful metaphysic, in theology, seems to border on heretical (ie Edwards, Berkeley). Similar to pantheism and emanation and poor distinction between thought, being and reality. Having a mental picture of an object is not grounds to assert that all reality is mental even though the mental plays an obviously key role in our perception of reality.
Hegel: powerful thinker whos ideas, to paraphrase That Individual, would have been brilliant had they been posited as an elaborate theory, but Hegel’s assertion that his philosophy was reality turns his ideas from interesting to absurd and even mad. Chilling ideas on the state, freedom and morality which laid the groundwork for a very bloody 20th century. Thoughts on the nature of reality similar to Heraclitus IE all is flux. History, the Real, Absolute Spirit all powerful ideas that need to be taken seriously as a system of thought.
Critical realism: primary viewpoint of Christianity – God exists independently of our thought or perception of Him. Stratification of truth (T.F. Torrance) distinguishes between kinds of truth IE truth of being, truth of relation, truth of statement. Operation of the human mind naturally realist – the words we employ point to the reality for which they stand rather than themselves. Our mind does not create reality but rather accepts the reality forced upon it, either in natural science or theology.