Philosophy of Cognitive Science ( 06 - 02483 ) Justificationism and Anti - justificationism Handout ( 2007 – 2008 )

A justification of some statement is an argument which has that statement as its conclusion, but not every such argument is a justification. Consider the argument shown in Fig. 1 (based on one found in Moser’s book Empirical Justification (1985), p. 23). What would make this a justification of the statement, ‘Swimming is going to be dangerous today’? For it to be a justification the argument would have to be valid and the premises would have to be justified in some way. Arguments have to contain a finite number of steps and so not every statement can be justified by being inferred from one or more further statements. This point is made, for example, by Popper in the right-hand side of his table of ideas shown in Table. 1. (This table occurs in several of Popper’s writings, namely Unended Quest, [10, p. 21], Objective Knowledge, [9, p. 124] and Conjectures and Refutations, [8, p. 19].) You would think that this point was so obvious that everyone would accept it, but this is not the case. For example, in his Sceptical Essays (1928) Bertrand Russell wrote: