(This must have been discussed some time ago at length, but could not locate it.)
As Don quoted (from this thread)
Horace for reference:
Latin
inter spem curamque, timores inter et iras
omnem crede diem tibi diluxisse supremum:
grata superveniet quae non sperabitur hora.
me pinguem et nitidum bene curata cute vises
cum ridere voles, Epicuri de grege porcum.
English (Loeb Classics)
Amid hopes and cares, amid fears and passions,
believe that every day that has dawned is your last.
Welcome will come to you another hour unhoped for.
As for me, when you want a laugh, you will find me in fine fettle,
fat and sleek, a hog from Epicurus’s herd.
***
I read this as creating a contrast between fear and the resultant asceticism of the Cynics, vs the "fettle" (good condition and health) of the Epicureans, when having enough to eat (and having some fat stores (rather than skin and bones) is helpful ahead of time when sickness comes because the body has that to use) and the laughter seems to be a reference of lightheartedness.
