MIND or MENS or SEMs is the ability to know, the possibility of knowing.
At one level the things we know are beings and each human is a being. This is the level of Buddhist ‘conventional truth’ – ie the conventional truth about a thing, that is is, that we are. At this level we can talk of God as ‘the supreme being’.
At a deeper level, any thing that we know is not a being but a becoming and each human being is a becoming. This is the level of Buddhist ‘ultimate truth’ – ie the ultimate truth about a thing, that it is ’empty’, that we are ’empty’ – ie empty of svabhavasiddhi, of the power of ‘self-being’, of ‘a-seitas’ (from-self-ness), ie it is (we are) the effect of cause – not some long-ago cause but of a cause present each instant. Everything is (we all are) ‘ab-alio’ (from non-self, from other). At this level we say God is being but we become; God alone is, things and people become.
With regard to mind as possibility of knowing (and of knowing this) there is one thing we know with absolute certitude tho (as Ibn’ Arabi says) most people find it difficult since the only way of knowing it as a ‘home truth’ (in Zen terms) and not just as something we are told by other people, which is only ‘bought treasure’, is by meditation and it is the meditation (not the obvious truth to which meditation is a gate) which people find difficult. Ch’an/Zen developed out of this difficulty as a method for teaching novices to know it for themselves, to know the moon and not the pointing-finger.