If its deterministic, but cannot be simplified and modelled by anything smaller than itself (imagine a simulator that modelled every atom - it would have to hav

If its deterministic, but cannot be simplified and modelled by anything smaller than itself (imagine a simulator that modelled every atom - it would have to have more atoms than it was modelling) ... then does it matter? That is, it may be deterministic but fundamentally unpredictable in practice. See Dennets 'freedom evolves' for a long discussion of this.