Just an info: Focusing mind at the gut level is not specific to Zen meditation but is instead part of Yoga Sutras of Patanjali (https://en.wikipedia.org/wiki/Yo

Just an info: Focusing mind at the gut level is not specific to Zen meditation but is instead part of Yoga Sutras of Patanjali (https://en.wikipedia.org/wiki/Yoga_Sutras_of_Patanjali https://en.wikipedia.org/wiki/Yoga_Sutras_of_Patanjali) from which all these techniques are derived from. Specifically it is focusing on the 7 centres of energy called Chakras. The gut level thing you talk about is called the Manipura in Sanskrit or the Solar Plexus Chakra in English transliteration.