Damian asked:

What is Descartes' view on how humans make errors in judgement and how they can avoid doing so?
What are Descartes' two reasons for believing that God is not to blame because humans make errors
in judgement? I think it is in Meditation IV. Please help!

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Descartes raises the question of how errors of judgement are possible in the Fourth Meditation. But
the complete answer is only given in the latter part of the Sixth. So you have been looking in the
wrong place!

How does the problem arise? The foundation of human knowledge and the refutation of scepticism,
according to Descartes, depends upon the existence of a perfect God who is not a deceiver. It is only
for this reason that we can have confidence that our perceptions correspond to an external world
outside us. It is only for this reason that we can have confidence that our sense of judgement, which
includes our sense of what is the best explanationof a given piece of evidence, is a reliable guide to
how things really are.

But if all that is true, how is it that human beings make errors in judgement, as they undoubtedly do?
Why does God allow us to be deceived? It cannot be malice or lack of power, because God is
all-good and all-powerful. Surely, if he'd wanted to, he could have made our power of understanding
in such a way that we always made the correct inferences. He could have made our senses in such a
way that they always gave accurate information about the world outside us.

True to the style of the Meditations,Descartes starts off by considering several responses, then
rejecting them as not fully satisfactory. Only God is perfect. I cannot know God's unfathomable
purposes, I am only a small part of the whole picture, and so on. You can skip this. It is part of the
standard fare that was served up (and still is) in response to the Problem of Evil. The first substantial
part of Descartes' answer concerns the will. The second part involves a fascinating discussion of how
the human senses operate.

I recently quoted a section from Descartes' discussion of will in my online notebook at The Glass
House Philosopher (see the page for 13th March 2000). We exercise our will when we choose what
to do, or choose what to believe. Now there is a simple way to avoid errors in judgement: Do not
make any judgement unless the object of your judgement is presented so 'clearly and distinctly' that
you cannot possibly be in error. This is the famous 'Method of Doubt' which Descartes has been
following in his Meditations.If human beings stuck to this principle, they would never go wrong.

The problem is - and this is the first part of Descartes' answer - we haveto make judgements every
day about things which are uncertain. You give it the best shot, only sometimes your best shot
misses. Weather forecasters are regularly blamed for making wrong predictions. But they are only
giving it their best shot.

Now it would be easy to think that Descartes answer here is complete in itself. We exercise our wills
in making a judgement, even though we can't be sure of being right, because practical circumstances
force us to. But there's an obvious objection: Why hasn't God, who does not wish us to be deceived,
arranged the world in such a way that we can always be certain when we make judgements? Why
can't our senses convey 100 per cent reliable knowledge of everything we need to know?

Descartes answer is that if you think about what this entails, you will see that it is impossible, even for
a God who is all-powerful and all-good. Descartes first point is illustrated by a child's innocent
question, 'Ma, why does the sun look so small when it's really so big?' Ma's answer - if she happens
to be a philosopher - is, 'How would the sun have to look in order to look as big as it really is?!'

If you think about how the senses of finite, space-occupying beings would have to operate in any
possible world, you will see that it would be impossible for the senses to convey accurate information
simply on the basis of the way things seem, without our having to use our understanding and
judgement, for example, in calculating the sun's true size from astronomical observations.

Descartes second point involves a fairly detailed description of how human bodies are constructed,
although it doesn't depend on contingent facts about human physiology. It would apply equally well to
Martians. Our senses operate in accordance to the laws of nature. The link-ups, when they are all set
up correctly, function as a reliable source of knowledge. However, the very fact that there is a chain of
causes and effects in between an object and our perception which gives rise to knowledge of that
object means that it is impossible, without violating the laws of nature, to avoid situations where
something goes wrong in the process. For example, the very nerves which reliably tell us when we
have hurt our foot, convey the false information to the amputee that he has pain in a foot which is not
there.

- It would be interesting to speculate whether Descartes' original and powerful response to the
problem of error could be extended to the problem of errors in moraljudgement, and thus provide a
basis for the solution of the Problem of Evil.

Geoffrey Klempner