  A basic issue concerning the empirical statues of Daltonian atomism was already pinpointed in an early exchange between Dalton (1814) and Berzelius (1815). Dalton was keen to present himself as the Newton of chemistry. In his view, just as Newton had explained Kepler’s laws with his new mechanics, so he, Dalton, had explained the laws of proportion with his atomism. Without atomism the joint truth of the three laws of proportion is a mystery. Berzelius questioned the experimental grounds for assuming anything stronger than the laws of proportion, since, he argued, all of the chemistry could be accommodated by the latter. That is, nothing testable by the chemistry of the time follows from Dalton's atomic theory that does not follow from the laws of proportion plus the experimental law of combining volumes for gases.