Editing Raven paradox (section)

====Good's baby====
In his proposed resolution, Maher implicitly made use of the fact that the proposition "All ravens are black" is highly probable when it is highly probable that there are no ravens. Good had used this fact before to respond to Hempel's insistence that Nicod's criterion was to be understood to hold in the absence of background information:<ref>{{cite journal |last1=Good |year=1968 |title=The White Shoe qua Red Herring is Pink |journal=The British Journal for the Philosophy of Science |volume=19 |issue=2 |pages=156–157 |jstor=686795 |doi=10.1093/bjps/19.2.156 |first1=I. J. }}</ref>

{{quote|...&nbsp;imagine an infinitely intelligent newborn baby having built-in neural circuits enabling him to deal with formal logic, English syntax, and subjective probability. He might now argue, after defining a raven in detail, that it is extremely unlikely that there are any ravens, and therefore it is extremely likely that all ravens are black, that is, that <math>H</math> is true. "On the other hand," he goes on to argue, "if there are ravens, then there is a reasonable chance that they are of a variety of colours. Therefore, if I were to discover that even a black raven exists I would consider <math>H</math> to be less probable than it was initially."}}

This, according to Good, is as close as one can reasonably expect to get to a condition of perfect ignorance, and it appears that Nicod's condition is still false. Maher made Good's argument more precise by using Carnap's theory of induction to formalize the notion that if there is one raven, then it is likely that there are many.<ref>{{cite book | editor-first=Christopher |editor-last=Hitchcock| title=Contemporary Debates in the Philosophy of Science |publisher=Blackwell |first=Patrick |last=Maher |year=2004 |chapter=Probability Captures the Logic of Scientific Confirmation |pages=69–93 |chapter-url=http://patrick.maher1.net/pctl.pdf |archive-url=https://ghostarchive.org/archive/20221009/http://patrick.maher1.net/pctl.pdf |archive-date=2022-10-09 |url-status=live}}</ref>

Maher's argument considers a universe of exactly two objects, each of which is very unlikely to be a raven (a one in a thousand chance) and reasonably unlikely to be black (a one in ten chance). Using Carnap's formula for induction, he finds that the probability that all ravens are black decreases from 0.9985 to 0.8995 when it is discovered that one of the two objects is a black raven.

Maher concludes that not only is the paradoxical conclusion true, but that Nicod's criterion is false in the absence of background knowledge (except for the knowledge that the number of objects in the universe is two and that ravens are less likely than black things).