after truth, and on that very account hold it disgraceful to
assent to what is false. I do not deny that I make slips, but we must
deal with the _sapiens_, whose characteristic it is never to err in
giving his assent (66). Hear Arcesilas' argument: if the _sapiens_ ever
gives his assent he will be obliged to _opine_, but he never will
_opine_ therefore he never will give his assent. The Stoics and
Antiochus deny the first of these statements, on the ground that it is
possible to distinguish between true and false (67). Even if it be so
the mere habit of assenting is full of peril. Still, our whole argument
must tend to show that _perception_ in the Stoic sense is impossible
(68). However, a few words first with Antiochus. When he was converted,
what proof had he of the doctrine he had so long denied? (69) Some
think he wished to found a school called by his own name. It is more
probable that he could no longer bear the opposition of all other
schools to the Academy (70). His conversion gave a splendid opening for
an _argumentum ad hominem_ (71).

Sec.64. _Quadam oratione_: so Halm, also Bait. after the best MSS., not
_quandam orationem_ as Lamb., Orelli. _De ipsa re_: cf. _de causa ipsa_
above. _Respondere posse_: for the om. of _me_ before the infin, which has
wrongly caused many edd. either to read _respondere_ (as Dav., Bait.) or to
insert _me_ (as Lamb.), see n. on I. 7.

Sec.65. _Studio certandi_: = [Greek: philoneikia]. _Pertinacia ... calumnia_:
n. on 14. _Iurarem_: Cic. was thinking of his own famous oath at the end of
his consulship.

Sec.66. _Turpissimum_: cf. I. 45, _N.D._ I. 1. _Opiner_: _opinio_ or [Greek:
doxa] is judgment based on insufficient grounds. _Sed quaerimus de
sapiente_: cf. 115, _T.D._ IV. 55, 59 also _De Or._ III. 75 _non quid ego
sed quid orator_. _Magnus ... opinator_: Aug. _Contra Acad._ III. 31 qu.
this passage wrongly as from the _Hortensius_. He imitates it, _ibid._ I.
15 _magnus definitor_. _Qua fidunt_, etc.: these lines are part of Cic.'s
_Aratea_, and are quoted in _N.D._ II. 105, 106. _Phoenices_: the same fact
is mentioned by Ovid, _Fasti_ III. 107, _Tristia_ IV. 3, 1. _Sed Helicen_:
the best MSS. om. _ad_, which Orelli places before _Helicen_. _Elimatas_:
the MSS. are divided between this and _limatas_. _Elimare_, though a very
rare word occurs _Ad Att._ XVI. 7, 3. _Visis cedo_: cf. n. on 38. _Vim
maximam_: so _summum mu