Siger of Brabant
Questions on Aristotle’s Metaphysics 1
On Fables and Falsehoods in Religion
Text 1: Whether the Custom of Hearing Falsehoods Makes One Believe Them?
1. It seems that it does not, because in Bk. 2 of the De anima, in giving the difference
between believing (opinari) and imagining, Aristotle says that it is up to us to imagine that
something is thus or not thus, but to believe it is not up to us. However, if the custom of hearing
falsehoods were to make us believe them, it would be up to us to believe that something is thus or
not thus. Therefore, etc.
2. Again, custom cannot remove something natural, as Aristotle observes when he says that
nature does not become accustomed to contraries. But the first principles are naturally known to
us, as the Commentator intended above. Therefore the custom of hearing the opposites of first
principles cannot produce belief in them.
3. Again, we form an opinion about a real thing from what appears to us concerning it, and
the same things always appear to us concerning a real thing. For this reason, to become
accustomed to the opposites of those things which appear to us concerning a real thing cannot
make us believe them.
[On the contrary], Aristotle intends the opposite position in the letter of the text. For he says that
“we demand the language we are accustomed to, etc.”
[Response]: I say to this that the custom of hearing falsehoods, even the opposites of those things
which are self-evident (per se nota), can cause belief in them. This is what Aristotle proves here
through its effect. For those things in human Laws which one is accustomed to hear, although
fabulous and false, are more tenacious in the soul than are the true things in them. The reason
why false and fabulous things are sometimes handed down in human Laws is because the
Lawgiver does not always posit things according to what is believed from first principles, but
according to what is more able to make citizens fit for good morals. But what is false and
fabulous can sometimes make human beings fit for the good, because according to Aristotle in
Bk. 10 of the Ethics, some people are by nature fit for goodness, whereas others become good
through instruction, and others are made good by lashes and threats, to the extent that just as
sensation seeks after what is delightful, so too does it flee what is sorrowful. And therefore in the
Law of Pythagoras it was handed down as a threat that the soul of a good human being after death
would enter another good body, whereas the soul of an evil person would enter the body of
another beast; which was not true, but was posited to inspire terror.
Translation © Deborah L. Black, 2013. From the text edited by A. A. Maurer in “Siger of Brabant on
Fables and Falsehoods in Religion,” Mediaeval Studies 43 (1981): 515–30, Appendix, 527–30.
2De anima 3.3.427b14–21. Siger of Brabant, Questions on the Metaphysics 2
The reason why the custom of hearing falsehoods makes one believe them is this: that to
hear something—and especially from someone famous—constitutes a sort of probable argument;
for this reason, authority is also a dialectical topic. Therefore, from such authority, or by hearing
things from someone famous, as much as through a probable argument, a habit which is an
opinion is formed. And with the multiplication of probable arguments, opinion is multiplied. And
since by being accustomed to hearing them some false things are multiplied as if they were an act
of probable reasoning, it is reasonable for the opinion concerning these false things to be
confirmed and multiplied in those hearing them. But the custom of hearing such things from
childhood especially makes one believe them, because children, on account of the weakness of
their intellects, cannot adjudicate the truth. And according to what the Commentator says on this
passage, custom in such things can make one believe the opposite of first principles and of self-
evident propositions, as he understood Avicenna to have done. For on account of custom in such
matters, Avicenna was led to deny that forms have matters which are proper to them, and
conceded that a human being could be generated from earth. But the reason why the custom of
hearing falsehoods makes one believe the opposite of first principles is because someone
generally possessing a habit of the intellect is disposed to what is commensurate with that habit.
But the opposites of the first principles are commensurate with the intellect which has been
habituated by the habit of hearing falsehoods. For first principles are in some way naturally