It seems to be implicitly assumed that additive particles like too or also are semantically equivalent. For instance, both versions of (1) are taken to presuppose that some salient alternative to Emma went to Germany. However, there are cases where the two particles cannot be freely substituted, as in (2). This suggests that there is more to the meaning of an additive particle than standardly assumed. I argue that the difference between too and also in English can be captured in terms of a contrast relation that also is able to express but too is not. Besides further investigation of the exact differences, I am also exploring the cross-linguistic variation of additive particles along these lines. For instance, in languages with only one prominent additive like German (auch) and Spanish (tambien), the respective particle seems to pattern with too, whereas languages that resemble English in having at least two high frequency elements, for example Korean (-to and ttohan), seem to display the same split.
(1a) [Emma]F went to Germany too.
(1b) [Emma]F also went to Germany.
(2) A: This is Krypto the Superdog. He has all the superpowers Superman has.
a. B: He’s also [a dog]F.
b. B: #He’s [a dog]F, too.
Göbel, A. (2016). Dividing Additives: On too, also and German auch. Talk at SNEWS 2016 @ Brown University, November 2016. [handout]