An experience that sustained observation may eventually bring forth: emptiness is not absence. When attention shifts from what is filled to what is empty — between two thoughts, between two breaths, between two objects — a particular quality appears.
This quality has been named by several traditions. Buddhists speak of śūnyatā. Christian contemplatives speak of nada, the dark night. The Laboratory takes no position on these readings and does not see in them a single reality: it notes only, within its own field, that observed emptiness is not experienced as a lack, but as a presence of another order.
Practically, learning to observe this emptiness modifies one’s relationship to what “fills” it. Thoughts, emotions, sensations appear against a ground — a ground that is no longer invisible. This structure modifies the quality of presence to oneself.
This is probably one of the most fertile observations that sustained practice can bring forth. It requires no adherence to a doctrine; it requires only having consented to explore what one had taken for emptiness.