Final answer:
Justification of beliefs should remain open to new evidence, especially concerning empirical or revolutionary claims. Contextualism highlights that the required level of justification is context-dependent. The web of justified beliefs, including those formed through testimony, are subject to continual assessment and adaptation as new information arises.
Step-by-step explanation:
Justifying a belief must allow for new evidence especially when considering empirical claims or when new information challenges long-held assumptions. This is rooted in the principle that extraordinary claims require extraordinary evidence. In everyday life, the justification for beliefs can change as we receive new testimony or experiences that challenge or support our current understanding.
Philosopher G.E. Moore posited that we don't need absolute certainty to claim knowledge; practical examples, such as observing a bird, show that knowledge can exist without certainty. This is aligned with the concept of contextualism, where the level of justification needed can depend on the context, such as requiring higher certainty from medical diagnoses than casual recollections.
In the realm of epistemology, foundationalists argue that there must be an endpoint in the justification of beliefs, while others assert that beliefs are justified through an interconnected web of other justified beliefs. For instance, testimony, which refers to relying on others' statements, is a practical way we form beliefs. In evaluating the credibility of testimony, we consider the reliability of sources, often preferring those with expertise or experience.
Despite considering someone an expert, it is essential to recognize that even expert testimony can be flawed. Hence, beliefs should remain open to reevaluation in the light of new evidence or when there is conflicting testimony. Lastly, the correspondence of beliefs to reality and consistency with other accepted truths is a standard by which to measure the utility of those beliefs.