The Herbrand universe serves as the universe in the Herbrand structure.
U = {c, fc, ffc, fffc, ...}
fc → fc, ffc → ffc, ...
c → c
; Flum, Jörg; Thomas, Wolfgang (1996). Mathematical Logic. Springer. ISBN 978-0387942582.
$_$_$DEEZ_NUTS#0__subtitleDEEZ_NUTS$_$_$