If you think about for example, proportionality and beauty, things like that, these seem to be some kind of representations of a kind of unity.

I think it's important to realise that what happens in Neo-Platonism beginning with Plotinus and Porphyry and then going on for the next several centuries, is a real kind of contest for the ideas and convictions of the intelligentsia of the later Roman Empire. So that you have Christians slowly converting more and more powerful people until of course actually Constantine and then other emperors after him, become Christian, and the empire becomes a Christian empire rather than Pagan empire.

Assuming there is an intellect, we're clearly not this universal intellect or we would know it. So that's one function of soul.

People often talk about Plotinus' system. The reason they do this is that Plotinus postulated a kind of series or chain of principles, so at the top there's what he called the One. Below the One is what he called Intellect. Below Intellect is Soul, and the effect of the soul is the physical world that we actually live in.

Al-Ghazali is the most important philosophical theologian of classical Islam, and Moderation in Belief is among his most important works. It sets out al-Ghazali's Ash?arite theology with unusual clarity and provides important background for such well-known works as his autobiographical Deliverance from Error and his attack on Avicenna in The Incoherence of the Philosophers. This first English-language translation, with notes that bring out the argumentation and background of the work, is thus very much to be welcomed.

Plotinus, when he thinks about mind or intellect, the Greek word is 'nous', he thinks about something that's very different, it's much more elevated and special, more abstract, you might say more philosophical than the very broad range of mental events that we talk about in contemporary philosophy of mind.

This is in a way the most important thing about soul is that it's a kind of principle which mediates between the universal intellect and the material world.