It is argued that neither the "theory-informity" of observations nor the Quine-Duhem thesis pose any in principle threat to the objectivity of theory evaluation. The employment of exploratory theories does not generate incommensurability, but on the contrary is responsible for the mensurability and commensurability of explanatory theories, since exploratory theories enable scientists to make observations which are critical in the evaluation of explanatory theories. The employment of exploratory theories and other auxiliary hypotheses does not enable a theory to always accommodate (...) recalcitrant observations to preserve evidential equivalence with a rival theory. Explanatory theories become rapidly degenerating if exploratory theories or other auxiliary hypotheses which inform the original confirmation base are modified to accommodate recalcitrant observations. (shrink)

(i) Scientific realism is primarily a metaphysical doctrine about the existence and nature of the unobservables of science. (ii) There are good explanationist arguments for realism, most famously that from the success of science, provided abduction is allowed. Abduction seems to be on an equal footing, at least, with other ampliative methods of inference. (iii) We have no reason to believe a doctrine of empirical equivalence that would sustain the underdetermination argument against realism. (iv) The key to defending realism from (...) the pessimistic meta-induction is that we have greatly improved our capacity to understand the unobservable world over recent centuries. (shrink)