Mind is necessarily seamless and undivided, while the experiencing ego or life is what it is through a network of boundaries and un-crossable or one-way barriers. These cannot be 'natural' barriers, say between operational levels of complexity, necessary reductions, since all such are themselves within mind - or if you will, they can only do what they are required to do from inside mind. Therefore the divisions that generate experience are within mind; they are not ideas but a kind of spacing for which we have no analogy or model.