I may illustrate how I differ from most philosophers by quoting the title of an article by Mr H. Hudson in Mind of April 1956. His article is entitled, ‘Why we cannot witness or observe what goes on “in our heads".' What I maintain is that we can witness or observe what goes on in our heads, and that we cannot witness or observe anything else at all.
Source: My Philosophical Development, chap. ２,1959
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