651. I cannot be making a mistake about 12
x 12 = 144. And now one cannot contrast mathematical
certainty with the relative uncertainty of empirical propositions. For the
mathematical proposition has been obtained by a series of actions that are in
no way different from the actions of the rest of our lives, and are in the same
degree liable to forgetfulness, oversight and illusion.
12 x 12 = 144 –
substituting one
set of terms for another – does not amount to certainty
what we have here
is a practise – a convention – a game –
not a certainty
and yes –
‘the mathematical proposition has been
obtained by a series of actions that are in no way different from the actions
of the rest of our lives, and are in the same degree liable to forgetfulness,
oversight and illusion.’ –
and this is to say –
the ground of any proposal – of any
proposition –
is uncertainty
