 On some readings of “differ in meaning”, any big difference in theory generates a difference in meaning. On such readings, the connectives do indeed differ in meaning between advocates of the different all-purpose logics, just as ‘electron’ differs in meaning between Thomson’s theory and Rutherford’s; but Rutherford’s theory disagrees with Thomson’s despite this difference in meaning, and it is unclear why we shouldn’t say the same thing about alternative all-purpose logics. (Field 2009)