The Salmon of Knowledge

The story of the Salmon of Knowledge is, today, perhaps the most familiar from the Fenian Cycle tales. It tells how the young Fionn gained his power and wisdom by accidently tasting part of a magical salmon. But older variants tell a different story. According to one 8th century text:

When the Fianna band was at Badhamair on the bank of the Siúir river, Cúldubh the son of Ua Birgge came from the sí fort on Femen and took their cooked food from them. For three nights he did thus to them. The third time, however, Fionn knew and went before him to the sí fort on Femen. Fionn caught him as he entered the sí fort, so that he died over there. As Fionn stretched his hand towards him, a woman met him with a wet vessel in her hand after distributing drink juts before. And she closed the door on the sí for, and Fionn inserted his finger between the door and the post. Then he put his finger into his mouth. When he took it out again he began to utter an incantation; mystic knowledge illuminated him.

The notion that Fionn gained knowledge by hurting his thumb led to other interpretations – the slamming door motif did not survive long. The following account, from the 12th century, says that a man called Finnéices (éices translating as “seer”), possibly an ancestor of Fionn, was originally intended to eat the Salmon of Knowledge. The salmon itself may have received its wisdom by eating the nuts of hazel trees – which were believed to hold concentrated wisdom, and which are still used to make divining rods and wands for sourcing water – that had dropped into the River Boyne, which was particularly associated with magic and folklore.

For seven years (the poet) Finnéices had been on the Bóinn seeking the salmon of Féc’s Pool, for it had been prophesised to him that he would eat the salmon of Féc and that nothing would remain unknown to him after that.

"The salmon was caught and was entrusted to Demne for cooking, and the poet (file) told him not to eat anything of the salmon. The lad brought him the salmon after it had been cooked.

“Did you eat anything of the salmon, lad?” asked the poet.
“No,” said the lad, “except that I burned my thumb and then put it in my mouth.”
“What is your name, lad?” said he.
“Demne,” said the lad.
“Fionn is your name, lad,” said he, “and it is to you that the salmon was given to eat, and you are the Fionn truly.”

The lad then ate the salmon. That is what gave the knowledge to Fionn. When he used to put his thumb into his mouth… that which was unknown to him would be revealed."

The implication is clear: the old Fionn is an extension of young Fionn. The theme of renewal, regeneration, and the passing of ancient wisdom shines through the narrative. But there are other variants of the story of the Salmon of Knowledge.