Merriam-webster says empty is containing nothing, or unhabituated, unfrequented, not pregnant, Null sense, lacking reality substance, meaning or value. It calls be destitute of effect or force. It could mean devoid of sense, hungry, idleness, useless
Somehow, we tend to use it for the word Sunyata of Buddhism, maybe because it is one of the synonyms for void.
Sunyata or sunyata is not a state of emptiness, it points and refers to something beyond. The nearest probable word would equanimity. It is a doctrine from the Lotus sutra, and being in that state, can be a feature of reality, a meditative state or a phenomenological analysis of experience.
The eastern philosophy particularly Buddhism teaches that the world of forms is illusionary. Beyond that is a state, which can only be experienced it cannot be described in words or cognitively understood. It is a sense of being part of the infinite.
Peter Matthiessen a seeker shares and his insight received meditating on the hard rocks of Himalayas, that form is emptiness and emptiness is form. The simplest way to put it, would be experienced by awakening it from within. But cannot be conceptualized.
If you would like to try the meditation: feel free to DM
Further reading: the snow leopard by peter Matthiessen
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