Explain how one of Gettier’s original counter examples attacks the tripartite view of knowledge.

The tripartite view of (propositional) knowledge (call this view: TVK) is a view that wishes to give an analysis of constructions such as "X knows that p" where 'X' stands for a noun phrase referring to a person and 'p' is a placeholder for a sentence. According to TVK "X knows that p" iff (if and only if): 

X believes that p 

X is justified in believing that p 

That p is true 

(These conditions are all necessary and jointly sufficient) 

Edmund Gettier (1963) proposed the following counterexample to this view: 

Suppose two people A and B are going for a job interview. A has been told by some authoritative individual in the company that B is going to get the job. A has also just seen B count out all of the coins in their pocket, they totalled 10. A believes that: 

(i) B is going to get the job and B has 10 coins in their pocket

A infers from (i) to (ii): 

(ii) The person who is going to get the job has 10 coins in their pocket

Suppose, however that A will in fact get the job. And, not only that, A happens to have 10 coins in their pocket. (ii) is therefore true, A believes (ii), and A is justified in believing it because they inferred it from premises that were themselves justified. However, intuitively we wouldn't want to say that A knows (ii). So we have a case where A has a justified true belief that (ii) but A does not know that (ii).