Oscar Wilde wrote that,

“One should either be a work of Art, or wear a work of Art.”

Charles Baudelaire defined the dandy, in the later “metaphysical” phase of dandyism, as one who elevates æsthetics to a living religion, that the dandy’s mere existence reproaches the responsible citizen of the middle class:

“Dandyism in certain respects comes close to spirituality and to stoicism” and “These beings have no other status, but that of cultivating the idea of beauty in their own persons, of satisfying their passions, of feeling and thinking …. Dandyism is a form of Romanticism. Contrary to what many thoughtless people seem to believe, dandyism is not even an excessive delight in clothes and material elegance. For the perfect dandy, these things are no more than the symbol of the aristocratic superiority of mind.”

In 1836 Thomas Carlyle wrote:

“A Dandy is a clothes-wearing Man, a Man whose trade, office and existence consists in the wearing of Clothes. Every faculty of his soul, spirit, purse, and person is heroically consecrated to this one object, the wearing of Clothes wisely and well: so that the others dress to live, he lives to dress … And now, for all this perennial Martyrdom, and Poesy, and even Prophecy, what is it that the Dandy asks in return? Solely, we may say, that you would recognise his existence; would admit him to be a living object; or even failing this, a visual object, or thing that will reflect rays of light…”

Albert Camus said in L’Homme révolté (1951) that:

“The dandy creates his own unity by aesthetic means. But it is an aesthetic of negation. “To live and die before a mirror”: that according to Baudelaire, was the dandy’s slogan. It is indeed a coherent slogan. The dandy is, by occupation, always in opposition. He can only exist by defiance. Up to now, man derived his coherence from the Creator. But from the moment that he consecrates his rupture from Him, he finds himself delivered over to the fleeting moment, to the passing days, and to wasted sensibility. Therefore he must take himself in hand. The dandy rallies his forces and creates a unity for himself by the very violence of his refusal. Profligate, like all people without a rule of life, he is only coherent as an actor. But an actor implies a public; the dandy can only play a part by setting himself up in opposition. He can only be sure of his own existence by finding it in the expression of others’ faces. Other people are his mirror. A mirror that quickly becomes clouded, it’s true, since human capacity for attention is limited. It must be ceaselessly stimulated, spurred on by provocation. The dandy, therefore, is always compelled to astonish. Singularity is his vocation, excess his way to perfection. Perpetually incomplete, always on the fringe of things, he compels others to create him, while denying their values. He plays at life because he is unable to live it.”

I want to read
Nigel Rodgers (2012). The Dandy: Peacock or enigma?