Innate intelligence, common sense
If you had any mother wit, you would not look for a gas leak with a match.
You don't have the sense you were born with.
A Guinea pig i.e. someone to do the dangerous work.
A monkey wanted some chestnuts which were roasting in the ashes of the fireplace. A cat was sleeping on the hearth. To avoid getting burned, the monkey used the cat's paw to drag the chestnuts out of the ashes.