In coming to a judgement about the reliability of knowledge, we need to consider whether we are looking to:
1. verify that knowledge — i.e. judge that the knowledge that we want to rely on is either untrue or true — or
2. disafﬁrm that knowledge — i.e. judge that the knowledge that we want to rely on is either untrue or has not yet been shown to be untrue.
Veriﬁcationism takes an optimistic stance. It allows us to make the decision that knowledge is either true or false (and hence, after deciding which it is, whether knowledge can or cannot be relied upon).
By contrast, falsiﬁcationism takes a strongly sceptical stance where the only choice is either to reject knowledge as being untrue or (at best) decide to judge all knowledge as being provisional and thereby open to disafﬁrmation in the future.
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