  Moore was first drawn to philosophy through contact with McTaggart and under McTaggart's influence he fell briefly under the spell of British idealism, especially the work of F. H. Bradley. Thus when in 1897 he made his first attempt to win a Prize Fellowship at Trinity he submitted a dissertation on ‘The Metaphysical Basis of Ethics’ in which he acknowledges his indebtedness to Bradley and presents an idealist ethical theory. One element of this theory is what he calls ‘the fallacy involved in all empirical definitions of the good’, which is immediately recognisable as a precursor of his famous claim in Principia Ethica that there is a fallacy, the ‘naturalistic fallacy’, in all naturalistic definitions of goodness. This point indicates that although, as we shall see below, Moore quickly came to reject the idealist philosophy of Bradley and McTaggart, he held that their criticisms of empiricism, as represented by J. S. Mill's philosophy, were sound and he carried this hostility to empiricism forward into his mature philosophy. In this respect, therefore, his early idealist enthusiasm had an enduring impact on his thought.