The common law imposed aiding and abetting liability on a person (possessing the requisite intent) who facilitated any part - even though not every part - of a criminal venture. Accomplice liability attached upon proof of “[a]ny participation in a general felonious plan” carried out by confederates. 1 F. Wharton, Criminal Law §251, p. 322 (11th ed. 1912) (hereinafter Wharton) (emphasis added). Or in the words of another standard reference: If a person was “present abetting while any act necessary to constitute the offense [was] being performed through another,” he could be charged as a principal-even “though [that act was] not the whole thing necessary.” 1 J. Bishop, Commentaries on the Criminal Law §649, p. 392 (7th ed. 1882) (emphasis added). And so “[w]here several acts constitute[d] together one crime, if each [was] separately performed by a different individual[,] . . . all [were] principals as to the whole.” Id., §650, at 392. The Wharton treatise gave the following example of how multiple confederates could perform different roles in carrying out a crime. Assume, Wharton hypothesized, that several persons “act in concert to steal a man’s goods.” Wharton §251, at 322. The victim is “induced by fraud to trust ...