Ambition and fleas both jump high

Thoughts, like fleas, jump from man to man, but they don't bite everybody.

When ambition ends, happiness begins.

So, naturalists observe, a flea Has smaller fleas that on him prey; And these have smaller still to bite 'em, And so proceed ad infinitum. Thus every poet in his kind Is bit by him that comes behind.

Panurge had a flea in his ear. [Fr., Panurge auoyt la pulee en l' oreille.]

Then mimick'd my voice with satyrical sneer, And sent me away with a Flea in my ear.