With whose definition of knowledge does edmund gettier, the philosopher who challenged the tripartite definition of sentential knowledge, find to successfully state the necessary and sufficient conditions for someone's knowing a given proposition?

The sufficient conditions are given by Plato with definition of knowledge does Edmund Gettier.

Edmund Gettier published a 3-page paper which challenged the definition of knowledge which has been defined and accepted since Plato. According to Plato, to have knowledge of something the following conditions must be met: justification, truth and belief.  

This means that “justified true belief” also referred to as JTB defines knowledge of a claim. Gettier’s paper challenged this definition by presenting two examples which disproved the long-accepted definition of knowledge. One example showed that there are cases where one can have a justified true belief about something or claim without actually having knowledge of the same claim.                                                                        

bacteria that live on the ocean floor are sustained by phytoplankton. phytoplankton, microscopic marine photosynthetic organisms, have a vastly significant role to play not only in the marine food web of which they’re part of, but also on a more global scale. despite their infinitely small size in comparison to other marine organisms, these tiny creatures occupy an immensely important ecological niche: they are the foundation of the marine food web, and as primary producers, play key roles in supporting all other organisms in the marine environment, as well as in the regulation of the earth’s climate through the sequestration of carbon, oxygen production, and other related processes. phytoplankton account for roughly half of all global primary productivity; therefore, their significance extends far beyond the marine environment alone. there is an intriguing sense of irony in the realization that these tiny living beings that often live out their existence unnoticed and undetected by the rest of the world, have such a far-reaching impact on the lives of virtually all other living organisms on the planet, particularly on those in the marine environment. the world that we have become accustomed to has been and is continuously shaped by the workings of these miniscule yet vital “plants of the sea”.

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