Why it gets a separate word
Presence is not concentration, not relaxation, not mindfulness in the technique sense. It is the recognition that being aware is happening — and that this awareness is closer than any thought about it. Most of the cognitive work the mind does is about experience, not the experience itself; presence is what was already the case before that commentary started, and remains the case while it continues, and persists when it stops.
Tolle's instruction
Tolle's working instruction across his books is some version of: notice the next sense impression — the sound, the breath, the felt sensation of the body — and meet it without first naming it or comparing it to anything else. The naming and comparing is mind-activity; what does the noticing is presence. The instruction is repeated because presence is not a state to be reached and then occupied; it is the always-available ground that the mind continuously misses by attending to its own commentary.
Cross-traditional convergence
What Brother Lawrence's seventeenth-century practice of the presence of God names is structurally identical: the cultivation of awareness of the always-already-given as one moves through ordinary tasks. Just sitting in Zen is the same. Spira's being aware of being aware is the same. The traditions disagree about a great deal; on this they converge enough that the convergence is itself a piece of evidence.
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