The Celts and Their Aversion to Straight Lines

The Celts attitudinal individuality precluded nationality. They fought too frequently amongst themselves; inhabited a kindred system too individual, too undisciplined, too lacking in organisation to permit the global ambition necessary to Empire. They never created a lasting political nation: Ireland the most cohesive single Celtic national presence, owed any autonomy as much to the country's geography- a lone island territory- as to any national political impulse among the Irish people or their leaders.
Frank Delaney- The Celts.

To such an individual ethos, the subsuming of the person within the apparatus of a state machine is abhorrent to the entire sense of life, and the very success of a nation as an imperial power, dependent on efficiency and obedience, rather than a proof of that people's superiority is to the Celtic sense proof of that people's atrophied nature. They have surrendered to a dead abstraction- the glory of the state- and this hostility towards the surrender of self a dead abstraction mirrored in Nietzsche's words, "The state is the coldest of all cold monsters. Where a people still exists, there the people do not understand the state and hate it as the evil eye."

Delaney also notes that "Just as they never organised into one political unit, they never created a single religion or pantheon."
The necessity of a cohesive religious or philosophical belief system is also something alien to the Celtic sense of life. The living faith in life renders far less important a rational filter into which experience is placed and understood.
An amusing example of the above imperviousness to rigid belief systems is a friend's grandmother saying at a family gathering in a discussion of death, that, sure, didn't we believe we might be reincarnated as a cow, or bird, etc; a lifetime of immersion in Catholicism failing to penetrate her core with the belief that, no, Catholics aren't supposed to believe in re-incarnation.
Delaney also writes:

Celtic art combined the dark and uncanny with the abstract and simplicistic: above all else it responded to the natural world. They abhorred the straight line, pushed organic influences to deliciously abstracted infinity. In Celtic art are very few natural animals, most are fantastic...to the Greeks a spiral is a spiral and a face a face, and it is always clear where the one ends and the othre begins, whereas the Celts 'see' the face into the spirals or tendrils; ambiguity is characteristic of Celtic art.

By contrast, the Roman and British Empires could be described as exactly a faith in the straight line that the Celts abhorred. Another point of interest is what Delaney decribes as "the Celts' practical and mystical" sense of life. The Celtic mystical sense is wholly at odds with the idea of life as illusory or maya, or meditation designed to remove one's consciousness from its bonds to the natural world. The Celt's intimate connection with the natural world renders a desire to overcome it ridiculous; a diseased abstraction, and notions like Manicheanism, or gnosticism, which lead the thinker to posit a fallen world, the creation of a flawed demiurge, are again the product of slaves to reason, with an atrophied sense of the life-force that should course through the veins of their animal nature.