other propositions.


5.2 The structures of propositions stand in internal relations to one
another.


5.21 In order to give prominence to these internal relations we can adopt
the following mode of expression: we can represent a proposition as the
result of an operation that produces it out of other propositions (which
are the bases of the operation).


5.22 An operation is the expression of a relation between the structures of
its result and of its bases.


5.23 The operation is what has to be done to the one proposition in order
to make the other out of it.


5.231 And that will, of course, depend on their formal properties, on the
internal similarity of their forms.


5.232 The internal relation by which a series is ordered is equivalent to
the operation that produces one term from another.


5.233 Operations cannot make their appearance before the point at which one