Here's a way of setting out his argument.
We'll look at what main assumptions involved are.
First he assumes the principle of credulity is strongest in children.
Second, he points out that if our trust in testimony were based on experience as Hume
claims it is, it would be weakest in children.
And on that basis he concludes the principle of credulity is innate and
not based on experience.
And there's a bit of a wrinkle here, you might have noticed this because it looks
like Reid is talking about what children in fact do.
he's talking about the fact that they do trust other people's testimony.
Whereas it looks like Hume was talking about what people ought to do.
They ought not trust testimony without evidence
that other people are likely to be right.
But I think we can appreciate Reid's point here if we take him to be saying
look children trust other people's testimony,
they don't have any evidence that other people are likely to be right.
And it doesn't seem to be anything wrong with that.
It's kind of counter intuitive to say that children aught not be so trusting.
In fact Reid claims if we did abide by hume's principles, then he says no
proposition that is uttered in discourse would be believed and such distrust and
incredulity would deprive us of the greatest benefits of society.
And place us in a worse condition than that of the savages.
Scary stuff, if we were as skeptical and
doubting as Hume suggests that we should be.
So, I think that's the big dispute between Hume and Reid on the matter of testimony.
Is trusting other people something innate, as Reid argues, or do we need evidence of
the reliability of testimony before we're going to trust it as Hume claims.
An interesting thing is that Hume and Reid also seem to disagree
on the reliability of human testimony and the extent to which testimony really is
a reliable source of information, about how truthful people really are.
So in addition to the principle of credulity,
Reid also said that there's a principle of veracity.
He defined it as a propensity to speak the truth so as to convey our real sentiments.
And he went on to say that lying is doing violence to our nature.
So just as we're naturally trusting creatures, Reid says,
we're also naturally honest creatures.
So Hume would've challenged this.
He would've challenged this idea that we're hardwired for honesty.
And the way he would've challenged it is by appealing to all the different
kind of situations in which human beings end up testifying falsely.
