Wise Man. Prophet. Magician. Mad Man. Hermit. Elder. Seer.
Merlin as an image is most popularly remembered in relation to the Grail myths. His influence upon King Arthur, as wise man advising the rulers. He set the ultimate quest before man, that of seeking the Holy Grail, the sacred chalice, for which Merlin plays the Guardian. It is Sir Percival who recovers the Grail and from his heroic quest, re-unites all of the lands.
Disney representations of Merlin are most likely the most common recollection of his image. Followed secondly by those found in new age bookstores or in relation to sci-fi & fantasy paraphernalia.
The Merlin traditions are deeply concerned with that of a connection to nature, and all that makes up this world where we live. The forest, the animals that inhabit this earth, the lakes, rivers and oceans. The world we do see and the worlds we imagine.
Here are some modern logos using the symbolism of Merlin.