Sri Aurobindo
Letters of Sri Aurobindo
5. Planes and Parts of the Being
Fragment ID: 302
It is not so simple as that – but it [the overmind] can for convenience be divided into four planes – mental overmind and the three you have written (intuitive overmind, true overmind and supramental overmind), but there are many layers in each and each of these can be regarded as a plane in itself.