Tahafut_al-Tahafut-transl-Engl-van-den-Bergh

I say:
from His way and deviate from the path of His guidance,
denying His words: ‘I did not make them witnesses of the
creation of the heavens and the earth nor of the creation of
themselves, ‘ who think wicked thoughts about God, who
believe that the powers of man suffice to reach the essence
of the divine, who, deceived in their minds, believe that the
human understanding is competent to free itself from the
authority of the prophets and from obedience to them. For no
doubt they are now forced to acknowledge that the
quintessence of their thought is reduced to absurdities which
would make one wonder if they were told in a dream.
One who wants to enter deeply into these speculations must know that
much of what is firmly established in the speculative sciences seems at
first sight, and compared to the opinions the common man holds about
them, like the visions of a dreamer, as Ghazali truly says; many of these
truths are deduced from a different kind of premisses from that which
satisfies the masses; indeed there is no other way for anyone to become
convinced of their truth than that of comprehending them by logical proof
and evidence. If, for example, the common man, and even he who has
reached a somewhat higher degree of culture, is told that the sun, which
appears to the eye as being the size of a foot, is about a hundred and
seventy times bigger than the earth, he will say that it is absurd, and will
regard him who believes it as a dreamer; and it is difficult for us to
convince him through propositions which he can easily understand and
acknowledge in a short time. The only way, indeed, to attain such
knowledge is through deductive proof-that is, for the man who is amenable
to proof. If it is the case even with geometrical questions and
mathematical problems in general, that, when a solution is explained to
the common man, it will appear to him fallacious and open to criticism at
first sight and to have the character of a dream, how much more this will
be the case in the metaphysical sciences, since for this kind of knowledge
there are no plausible premisses which satisfy the superficial
understanding, by which I mean the understanding of the masses. One
might say that the final knowledge the understanding can reach will seem
to the common man at first sight something absurd. And this happens not
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