Question about None

Terry Reedy tjreedy at
Sun Jun 14 19:14:10 EDT 2009

Steven D'Aprano wrote:
> So-called "vacuous truth". It's often useful to have all([]) return
> true, but it's not *always* useful -- there are reasonable cases
> where the opposite behaviour would be useful:
> if all(the evidence points to the Defendant's guilt) then: the
> Defendant is guilty execute(the Defendant)
> sadly means that if there is no evidence that a crime has been
> committed, the person accused of committing the imaginary crime will
> be executed.

It seems to me that the absurd conclusion implied by the theorem
invalidates the theorem rather than supporting your point.  No evidence 
is only the endpoint of a continuum.  Suppose that 'all' is one teensy 
weensy bit of evidence. A drunked bystander gives a vague description 
that fits.  Or twenty years before, the defendent argued with the 
deceased and said 'I wish you were dead'. Should the person be executed? 
I say not.  You?

Of course, a person would only be a defendant in the absence of evidence 
under a depraved regime that would not much care if there were.

Try finding another 'reasonable case'.

Terry Jan Reedy

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