diaphero^ : in LSJ for its meaning "to differ"
(a sample used with infinitive)
mone^i te^i morphe^i me^ ouchi probata einai d.
my translation (they differed not to be sheep = they did not seem not to be sheep = they seemed to be sheep)
In this sample for diaphero^ + inf., I felt the <me^ ou> was the key. So I consulted Smyth for <me^ ou>.\
me^ ou :
/
--- oudeis po^pot' anteipen me^ ou kalo^s echein tous nomous (no one ever denied that the laws were excellent)(Smyth 1631, explaining about the infinitive with <me^ ou>) When a verb of denying, refusing, etc. is itself negatived, either directly or by appearing in a question expecting a negative answer, the infinitive generally has <me^ ou>. Here both the introductory clause and the dependent clause virtually have an affirmative sense.
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--- ouk an pithoime^n me^ ou tad' ekmathein (I cannot consent not to learn this)(Smyth 1633, explaining about <me^ ou> with the infinitive) Any infinitive that would take <me^ > may take <me^ ou> (with a negative force), if dependent on a negatived verb. Here <ou> is the sympathetic negative and is untranslatable. This use is often found with verbs and other expressions formed by <ou> (or a-privative) with a positive word and meaning "impossible", "difficult", "wrong", and the like.
--- ho^ste pa^sin aischune^n einai me^ ou suspoudazein (so that all were ashamed <i.e. felt it was not right) not to cooperate zealously)
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--- elegon oti ou dune^sointo me^ peithesthai tois Thebaiois (they said that they could not help submitting to the Thebans)(Smyth 1634., after the explanation of <me^ ou> from 1633.) Instead of <me^ ou> we find also <me^ > (rarely)
--- (an example of the form <to me^ > ) ephe^ ouch hoion t' einai to me^ apokteinai me (he said it was not possible to condemn me to death)
---- (an example of the form <tou me^ > ) he^ aporia tou me^ he^suchazein (the inability to rest) ...( think it is "inability not to rest)
By the samples in bold type I guessed "diaphero^" might be translated as "not be" or "not seem".
Then, I want to translate this passage. (Aristotle DE ANIMA)
my translation : "Why don't the elementary objects of the mind seem not to be phantoms ?" ot "Surely the elementary objects of the mind seem to be phantoms."τὰ δὲ πρῶτα νοήματα τί διοίσει τοῦ μὴ φαντάσματα εἶναι;