How to call someone stupid, like a sir

Poor Odysseus, lost at sea for about 20 years, finally comes to the court of the Phaecian king Alcinous, begging for a ship to take him home. Before sending him on his way, Alcinous organizes a feast and some competitions in his honour. All fun and games but all the poor guy can think of is how to get home faster, and then there's this bard, Demodocus, who sings a song about Odysseus himself and his great feats in the Trojan War which makes him weep like a baby.

Then one of the champions of the realms gets this crazy idea in his head to challenge the hero to take part in their games but he's to sulky to think about racing. The thug then claims that Odysseus must be somekind of fraud and not really a great man at all. At this, hero that he is, Odysseus reacts and calls the guy an oaf.

And here comes the good part. It's Homer, for crying out loud, so he's very elegant with his insults.
In the following lines, how to call someone stupid like a sir.

You, you’re a reckless fool—I see that. So,

the gods don’t hand out all their gifts at once,

not build and brains and flowing speech to all.

One man may fail to impress us with his looks

but a god can crown his words with beauty, charm,

and men look on with delight when he speaks out.

Never faltering, filled with winning self-control,

he shines forth at assembly grounds and people gaze

at him like a god when he walks through the streets.

Another man may look like a deathless one on high

but there’s not a bit of grace to crown his words.

Just like you, my fine, handsome friend. Not even

a god could improve those lovely looks of yours

but the mind inside is worthless.