one.

First, No. 5. All we know about THIS is that its OUTER portion
is empty: but we know nothing about its inner portion. Thus the
Square MAY be empty, or it MAY have something in it. Who can tell?
So we dare not place ANY counter in this Square.

Secondly, what of No. 6? Here we are a little better off. We
know that there is SOMETHING in it, for there is a red counter in
its outer portion. It is true we do not know whether its inner
portion is empty or occupied: but what does THAT matter? One solitary
Cake, in one corner of the Square, is quite sufficient excuse for
saying "THIS SQUARE IS OCCUPIED", and for marking it with a red
counter.

As to No. 7, we are in the same condition as with No. 5--we find
it PARTLY 'empty', but we do not know whether the other part is
empty or occupied: so we dare not mark this Square.

And as to No. 8, we have simply no information at all.

The result is

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