自由主義者德渥肯（Ronald Dworkin）認為把言論自由視為一種「積極自由」會得出荒謬的結論，因此不能成立。對此，魏斯特認為其「理解要求」（the comprehension requirement）可使得言論自由不變成「積極自由」，因此可成功回應德渥肯的質疑。筆者將證明德渥肯的主張言之成理，至於魏斯特的「理解要求」則仍會使得言論自由變成「積極自由」，因此無法成立。此外，筆者也將主張：我們必須以自由主義的「機會」（opportunity）概念來理解言論的散播，而且此一「機會」概念必須是一種「全有或全無」（all-or-none）的概念，以避免使得言論自由變成一種「積極自由」。 Feminists Caroline West and David Braddon-Mitchell argue that speech can be free insofar as its distribution is permitted or enabled, it can be understood, and it is not prevented from being considered. But Ronald Dworkin argues that the right to free speech, according to the feminist view, would be a "positive" right which liberals are unlikely to want to accept. West believes that her comprehension requirement will put some constraints by which we will acquire a conception that is consistent with the liberal conception of free speech. The central aim of this paper is to show why West's comprehension requirement is mistaken. This suggests that the right to free speech should be a "negative" one, which does not impose unacceptably illiberal duties on hearers. One way of expressing the right to free speech, in the familiar liberal language of negative rights, is this: that were speakers to speak, and were hearers to want to hear the idea the speaker expressed by so speaking, there is no government agent whose actions deprive speakers the opportunity for distributing that idea.