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Hugin and Munin

http://en.wikipedia.org/wiki/Hugin_and_Munin

Huginn and Muninn, sometimes Anglicized Hugin and Munin, are a pair of ravens associated with the Norse god Odin. Hugin and Munin travel the world bearing news and information to Odin. Hugin is "thought" and Munin is "memory". They are sent out at dawn to gather information and return in the evening. They perch on the god's shoulders and whisper the news into his ears. It is from these ravens that the kenning 'raven-god' for Odin is derived.

http://www.infoplease.com/dictionary/brewers/hugin-munin.html

“Perhaps the nursery saying, `A little bird told me that,' is a corruption of Hugo and Munin, and so we have the old Northern superstition lingering among us without our being aware of it.” —Julia Goddard: Joyce Dormer's Story, ii. 11. (See Bird.)
Source: Dictionary of Phrase and Fable, E. Cobham Brewer, 1894

http://www.octavia.net/vikings/odin.htm

Odin's quest for knowledge was never-ending. Upon his shoulders perched two ravens, Hugin ("Thought"), and Munin ("Memory"). These circled the Earth each day, seeing all, and then at night reported to Odin what they had learnt. He cherished them both, but particularly Munin, which seems to underscore the importance he placed on rune writing, record keeping, and honouring the heroic deeds of the past.

http://www.jpwalter.com/scholarship/huginandmugin.html

In these two ravens I see a mythic representation of the connection between thought and memory. Our ability to think allows us to access and make use of our memories. And our memories, whether they are naturally or artificially stored, represent that which we know, what we call knowledge. Just as Hugin and Munin are separate but closely related entities, thought and memory are discrete but connected cognitive functions.Thought allows us to make use of our memories by means of reminiscentia, while at the same time our memories serve as a machina memorialis, as the engine of thought.

http://www.theosociety.org/pasadena/odin/odin-16.htm

Hugin means mind in all the many connotations in which that word is commonly used: mental proficiency is only one of its meanings; it can also be used for purpose, intent, mood, attitude, disposition -- all of which apply to Hugin. Munin too has many meanings, memory being chief of these. Without memory there would be no modification of the mind. It is on such modification caused by cumulative experience that intelligence feeds and proficiency is gained, character is altered, and evolution proceeds. We are always building on the awareness of events gone by. But more than that: Munin also determines motivation, the primary factor in directing the mind and subsequent action. It is Hugin that is in danger of entrapment on its excursions, but the fear for Munin is eternal.

http://www.theosociety.org/pasadena/odin/odin-27.htm

Odin's two ravens, Hugin and Munin (mind and memory), "daily fly over the battlefield earth" and report back to Allfather by night. Here we again find mention of the gods' anxiety for Hugin, lest he fail to return. There is cogent reason for this. Mind entails choice: beings who possess this faculty, who have attained the function of intelligence and free will, as has humanity on earth, are faced with the options these present. They can, if they so choose, ally themselves totally with the matter-side of nature, the giants, in extreme cases severing their connection with their inner god, so that their characteristic contribution to the cosmic purpose is lost and the soul forgoes its opportunity to become immortal. Or they can gradually blend with the divine source of their existence. The critical choice is not made all at once; it is the cumulative effect of numberless small choices made through progressive stages of life. In the natural course of growth the soul unites each increment of experience with its divine source and so little by little merges with it.
So it is that at the end of a "day" of life, Hugin returns to Odin, bringing tidings of the manifest world and rejoining the divinity whence it originally flew. Its companion, Munin, is the container of all the record of events since the beginning of time. It is on the report of Munin that is built all attainment, as memory remains eternally as the foundation of future awareness.

http://www.sacred-texts.com/neu/poe/poe06.htm

20. O'er Mithgarth Hugin | and Munin both
Each day set forth to fly;
For Hugin I fear | lest he come not home,
But for Munin my care is more.