Aristotle's Metaphysics was the first major study of the subject of metaphysics - in other words, an inquiry into 'first philosophy', or 'wisdom'. It differs from Physics which is concerned with the natural world: things which are subject to the laws of nature, things that move and change, are measurable. In Metaphysics, the study falls on 'being qua being' - being insofar as it is being; the causes and principles of being, the causes and principles of substances.

These five very different Socratic Dialogues date from Plato's later period, when he was revisiting his early thoughts and conclusions and showing a willingness for revision. In Timaeus (mainly a monologue read by David Timson in the title role), Plato considers cosmology in terms of the nature and structure of the universe, the ever-changing physical world and the unchanging eternal world. And he proposes a demiurge as a benevolent creator God.

Here are the Socratic Dialogues presented as Plato designed them to be - living discussions between friends and protagonists, with the personality of Socrates himself coming alive as he deals with a host of subjects, from justice and inspiration to courage, poetry and the gods. Plato's Socratic Dialogues provide a bedrock for classical Western philosophy. For centuries they have been read, studied and discussed via the flat pages of books, but the ideal medium for them is the spoken word.

Here are three important but very different Dialogues from the Middle Period. Symposium, the most well-known in this collection, is concerned with the theme of love. In the house of Agathon, a group of friends - each very different in personality and background - meet to consider and discuss various kinds of love. Each one, Phaedrus, Pausanias, Eryximachus, Aristophanes (the playwright) and Agathon (a prize-winning tragic poet), presents his particular view in a short discourse.

The remarkable range of Plato's Dialogues is vividly demonstrated by these three works. It opens with Phaedrus, a highly personal discussion between Socrates (David Rintoul) and the young, love-struck Phaedrus (Gunnar Cauthery). They go for a walk outside the walls of Athens and, under a plane tree by the banks of the Ilissus, talk about love - erotic and 'Platonic' love. Socrates endeavours to steer Phaedrus away from infatuation and show him that real love is based on concern for the beloved.