Down in the Underworld, Odysseus meets and greets. Tiresias, although dead, still knows everything. Odysseus shouldn't do anything to Cattle. Bad things will happen if he does things to Cattle.
... - but harm them in any way, and I can see it now:
your ship destroyed, your men destroyed as well.
and even if you escape, you'll come home late
and come a broken man - all shipmates lost,
alone in a stranger's ship -
and you will find a world of pain at home,
crude, arrogant men devouring all your goods,
courting your noble wife, offering gifts to win her.
No doubt you will pay them back in blood when you come home!
But once you have killed those suitors in your halls -
by stealth or in open fight with slashing bronze -
go forth once more, you must ...
carry your well-planed oar until you come
to a race of people who know nothing of the sea,
whose food is never seasoned with salt, strangers all
to ships with their crimson prows and long slim oars,
wings that make ships fly.
The Odyssey, Book 11: The Kingdom of the Dead. Fagles translation, lines 127 - 143.
And you know what's going to happen. Odysseus doesn't make a habit of heeding predictions.