Direct Cut at the Root

The basis of attachment is the mistaken belief in the reality of thoughts, particularly regarding the existence of a person and an object. Thoughts are not grasped when they are seen to be unestablished, without thought there is no view or interpretation, and without view there is no emotional disturbance. Hence the direct and sudden way is recognising thoughts for what they are, how they conjure a world, and thus there is no identification with them. The gradual way leads to the same, but it is about calming the mind enough to be able to recognise how the process of thought-view-emotion-action-etc. happens.

So, when it comes to Zen, as a sudden teaching, it is simply about no-thought (or no-mind, etc.), that is cutting the root of delusion directly, i.e. seeing the nature of mind. Everything else apart from that are gradual skilful means.