⌊⌊So he can make sure he did of what it means ↺in this private way by having a priv. sens.’!⌋⌋ Making sure that you know what ‘seeing
red’ means is good only if you can make use of this knowledge in a future case. Now what if I see a colour again, can I say I knew made sure I knew what ‘red’
meant
was
so now I shall know that I'll recognize it correctly? In what sense is having said the words ‘this is red’ before a guarantee that I now see the same colour when I say again I see red