Eubulĭdes
（
Εὐβουλίδης). A native of Miletus and successor of Euclid
in the Megaric school. He was a strong opponent of Aristotle, and seized every opportunity of
censuring his writings and calumniating his character. He introduced new subtleties into the
art of disputation, several of which, though often mentioned as proof of great ingenuity,
deserve only to be remembered as examples of egregious trifling. Of these sophistical modes of
reasoning, called by Aristotle “Eristic syllogisms,” a few examples may
suffice.
1.
The Lying. If, when you speak the truth, you say, you lie, you lie: but you
say you lie when you speak the truth; therefore, in speaking the truth, you lie.
2.
The Occult. Do you know your father? Yes. Do you know this man who is
veiled? No. Then you do not know your father, for it is your father who is veiled.
3.
Electra. Electra, the daughter of Agamemnon, knew her brother and did not know him; she knew Orestes to be her brother, but she did not know
that person to be her brother who was conversing with her.
4.
Sorites. Is one grain a heap? No. Two grains? No. Three grains? No. Go on,
adding one by one; and if one grain be not a heap, it will be impossible to say what number
of grains make a heap.
5.
The Horned. You have what you have not lost: you have not lost horns;
therefore you have horns. In such high repute were these quibbles that Chrysippus wrote six
books on the first of them; and Philetas of Cos died of consumption which he contracted in
the close study which he bestowed upon them (
Diog. Laert. i.
111).
