E. Cobham Brewer 18101897. Dictionary of Phrase and Fable. 1898.
The horns of a dilemma. Lemma means a thing taken for granted (Greek, lambano, to take). Dilemma is a double lemma, a two-edged sword which strikes both ways, or a bull which will toss you whichever horn you lay hold of. A young rhetorician said to an old sophist, Teach me to plead, and I will pay you when I gain a cause. The master sued for payment, and the scholar pleaded, If I gain the cause I shall not pay you, because the judge will say I am not to pay; and if I lose my cause I shall not be required to pay, according to the terms of our agreement. To this the master replied, Not so; if you gain your cause you must pay me according to the terms of our agreement; and if you lose your cause the judge will condemn you to pay me.