  This paper discusses how theories can be assessed within the epistemological
viewpoint advanced by the Austrian physicist Ludwig E. Boltzmann. It builds
upon, and further develops, the perspective of Boltzmann's thinking as advanced
by Ribeiro and Videira (1998, arXiv:physics/9806011). Boltzmann's
epistemological viewpoint accepts that reality is real and proposes that
reality can be described by different points of view because his main
philosophical thesis states that scientific theories are images of Nature. We
present the historical context that witnessed the genesis of Boltzmann's ideas
and expand Ribeiro and Videira's (Ibid.) perspective by arguing that later in
his life Boltzmann realized the insufficiency of his thesis as justification
for theoretical pluralism and avoidance of dogmatism. Consequently, his
thinking went beyond epistemology, the nature of scientific knowledge, to
include realism, the nature of the represented objects.
