Plotinus is a neo-Platonist, so he would encourage us to go back to Plato.

In fact Plotinus does believe in divine providence, though when he talks about divine providence, he talks about that providence being exercised by the intellect and the soul of the world, rather than the One.

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.

Sometimes clichés are true.

What the soul is doing is kind of walking through the forms, and so our experience of thinking isn't normally this kind of pure intuitive insight that intellect gets, and that intellect must get right, because it's always identical to its objects, it's always the same as the forms that it's thinking about.

If you think about even very common examples like, say, something that you would build, like a clock or a car or a group of people trying to accomplish something, it fails when its unity breaks down. So when it stops having a single form, which is functioning all together, then it sort of falls apart into discrete elements.

The idea is that to grasp an idea like equality or justice, you can't look at the equal and just or unjust things in the world around you, you have to somehow ascend to or maybe remember some kind of idea of equality and justice and this would be a Platonic form, and it would be different from the things that partake in the form.