In Thomas Carlyle's book Sartor Resartus, just who or what was Sartor Resartus?
Thomas Carlyle's Sartor Resartus, although having a quasi-fictional form, is actually more a hybrid of picaresque and satire, much in the mode of Jonathan Swift's Gulliver's Travels, and consists more of extended diatribes than of connected narrative.
The phrase "sartor resartus" means "tailor retailored" and does not refer to one specific character, but rather to Carlyle's understanding of the nature of humanity as a whole.
Let us separate the metaphor into tenor and vehicle. On the literal level, a tailor both tailors (makes clothes) and is tailored (wears clothes tailored for him). What this refers to on the metaphorical level is that humanity both creates its own ideologies, cultures, and religions, but is at the same time shaped by these cultural constructs.
The protagonist, Diogenes Teufelsdröckh, undergoes many adventures, in which he discovers and undermines various rational systems and cultural constructs. Eventually, he realizes that his own path to the transcendent lies not in these artificial systems but in a mystical acceptance of the infinite. Carlyle affirms:
... know this of a truth: the thing thou seekest is already with thee, ‘here or nowhere,’ couldst thou only see!