Full Idea
To tell us that Galileo had 'incommensurable' notions and then go on to describe them at length is totally incoherent.
Clarification
'Incommensurable' means they can't be measured or compared
Gist of Idea
Galileo's notions can't be 'incommensurable' if we can fully describe them
Source
comment on Thomas S. Kuhn (Structure of Scientific Revolutions (2nd ed) [1962]) by Hilary Putnam - Reason, Truth and History Ch.5
Book Reference
Putnam,Hilary: 'Reason, Truth and History' [CUP 1998], p.115
A Reaction
How refreshingly sensible. Incommensurability is the sort of nonsense you slide into if you take an instrumental view of science. But scientists are continually aim to pin down what is actually there. Translation between theories is very difficult!