Full Idea
The considerations which make it necessary, as Berkeley saw, to give a phenomenalist account of material things, make it necessary also, as Berkeley did not see, to give a phenomenalist account of the self.
Clarification
'Phenomenalist' means 'in terms purely of experiences'
Gist of Idea
Berkeley needed a phenomenalist account of the self, as well as of material things
Source
comment on George Berkeley (Three Dialogues of Hylas and Philonous [1713]) by A.J. Ayer - Language,Truth and Logic Ch.7
Book Reference
Ayer,A.J.: 'Language, Truth and Logic' [Penguin 1974], p.167
A Reaction
Phenomenalism involves 'possible' experiences as well as actual ones. That could add up to quite a rich and stable account of the self, as opposed to Hume's notorious introspection, which only saw an actual shifting 'bundle' of experience.