“3. It is said that the I-activity is the root of all activities. From where the I-thought emerges, that in short is the heart.”
In the definition of the heart is placed as a corollary that the direct Sadhana for knowing the heart is the tracking down to the origin of the I-thought.
The Science of the Heart
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Ramana Maharshi 75
Indian religious leader 1879–1950Related quotes

“Power from natural agents may go by a short line, and then in its activity greater”
De Lineas, Anguilis et Figurisas quoted by A.C. Crombie, Robert Groseesteste and the Origins of Experimental Science 1100-1700 (1953) citing Baur, Ludwig (ed.) Die Philosophischen Werke des Robert Grosseteste, Bischofs von Lincoln (1912)
Context: Power from natural agents may go by a short line, and then in its activity greater... But if by a straight line then its action is stronger and better, as Aristotle says in Book V of the Physics, because nature operates in the shortest way possible. But the straight line is the shortest of all, as he says in the same place.

“I prefer thought to action, an idea to a transaction, contemplation to activity.”
Je préfère la pensée à l'action, une idée à une affaire, la contemplation au mouvement.
Louis Lambert (1832), as translated by Clara Bell

"New Maps of Hyperspace" (1989); originally published in Magical Blend magazine, also in The Archaic Revival: Speculations on Psychedelic Mushrooms, the Amazon, Virtual Reality, UFOs, Evolution, Shamanism, the Rebirth of the Goddess, and the End of History (1992) http://www.erowid.org/culture/characters/mckenna_terence/mckenna_terence_maps_hyperspace.shtml
Context: There is a spiritual obligation, there is a task to be done. It is not, however, something as simple as following a set of somebody else's rules. The noetic enterprise is a primary obligation toward being. Our salvation is linked to it. Not everyone has to read alchemical texts or study superconducting biomolecules to make the transition. Most people make it naively by thinking clearly about the present at hand, but we intellectuals are trapped in a world of too much information. Innocence is gone for us. We cannot expect to cross the rainbow bridge through a good act of contrition; that will not be sufficient.
We have to understand. Whitehead said, "Understanding is the apperception of pattern as such"; to fear death is to misunderstand life. Cognitive activity is the defining act of humanness. Language, thought, analysis, art, dance, poetry, mythmaking: these are the things that point the way toward the realm of the eschaton. We humans may be released into a realm of pure self-engineering. The imagination is everything. This was Blake's perception. This is where we came from. This is where we are going. And it is only to be approached through cognitive activity.
Source: Dealing with Complexity (1988), p. 111.

Source: All the Pretty Horses (1992)
Context: He thought he'd be an object of some curiosity but the people he saw only nodded gravely to him and passed on. He carried the bucket back into the store and went down the street to where there was a small cafe and he entered and sat at one of the three small wooden tables. The floor of the cafe was packed mud newly swept and he was the only customer. He stood the rifle against the wall and ordered huevos revueltos and a cup of chocolate and he sat and waited for it to come and then he ate very slowly. The food was rich to his taste and the chocolate was made with canela and he drank it and ordered another and folded a tortilla and ate and watched the horses standing in the square across the street and watched the girls. They'd hung the gazebo with crepe and it looked like a festooned brush-pile. The proprietor showed him great courtesy and brought him fresh tortillas hot from the comal and told him that there was to be a wedding and that it would be a pity if it rained. He inquired where he might be from and showed surprise he'd come so far. He stood at the window of the empty cafe and watched the activities in the square and he said that it was good that God kept the truths of life from the young as they were starting out or else they'd have no heart to start at all.

“if I am not actively creating something, then I am probably actively destroying something”
Source: Big Magic: Creative Living Beyond Fear

“I shall be active and vigorous even from my tomb.”
Eleven important sayings

“I always give 'rest to rest' and hope I will not retire from active politics.”
Chief Minister's speech to the media, rest for politics (14 December 2006)