|The Development of Galois Theory||MacTutor Index| The first
mathematician who published a commentary on Galois' two main
papers was Enrico Betti (1823-1892). In his 1852 publication
Sulla risoluzione delle equazioni algebriche, he presented
Galois' ideas in a more accessible manner, making a few
additions of his own. His main contribution was to fill in gaps
in certain proofs by Galois, Abel and Ruffini but he also
generalised some of Galois' group theoretical results. Like his
contemporaries, Betti certainly overemphasised the application
of Galois Theory to the solvability of equations, and he seemed
slightly confused over some group theoretical aspects. For
example, he does not start his proofs by defining a group G, but
instead normalises in some unspecified universe which leads to a
confusion of the group with its quotient groups. However, he
achieves some interesting results and advances the understanding
of group theory, for example by extending conjugation from
elements to subgroups. Furthermore, Bet