John Proctor at the beginning is a 𝘃𝗮𝗹𝘂𝗮𝗯𝗹𝗲 𝗺𝗲𝗺𝗯𝗲𝗿 of the community. He is a powerful man and he refuses to follow those he feels are hypocrites. However, his big mistake is that he has slept with Abigail. He is 𝗴𝘂𝗶𝗹𝘁-𝗿𝗶𝗱𝗱𝗲𝗻 and has a clear sense of personal integrity so regards himself as a 𝗳𝗿𝗮𝘂𝗱.
Proctor 𝗿𝗲𝗴𝗿𝗲𝘁𝘀 𝗵𝗶𝘀 𝗮𝗰𝘁𝗶𝗼𝗻𝘀 and is devoted to Elizabeth so he rejects Abigail's advances. Abigail is jealous of Elizabeth which sets the entire witch-hunt in motion.
Once the trials begin, Proctor realises he can stop the events but he must confess to adultery first. But he doesn't, because he is 𝘁𝗼𝗼 𝗽𝗿𝗼𝘂𝗱 and fears it would ruin his 𝗴𝗼𝗼𝗱 𝗻𝗮𝗺𝗲.
When Elizabeth is accused, Proctor names Abigail as a fraud. He finally admits his adultery to save his wife but his wife lies to protect him and therefore the testimony fails. This is the 𝗰𝗹𝗶𝗺𝗮𝘅.
In prison, Proctor initially 𝘀𝗮𝗰𝗿𝗶𝗳𝗶𝗰𝗲𝘀 𝗵𝗶𝘀 𝗶𝗻𝘁𝗲𝗴𝗿𝗶𝘁𝘆 to save his life by confessing, but in the end he refuses to sign the paper. This is because he cannot sacrifice the good name of others to live as he has too much integrity and he realises honour and truth is more important. In the end he is now 𝗴𝘂𝗶𝗹𝘁-𝗳𝗿𝗲𝗲 and finally 𝗿𝗲𝗰𝗼𝗻𝗰𝗶𝗹𝗲𝗱 to Elizabeth. His choice affirms his goodness and reveals selfish corruption of ideological forces that condemn him. His sacrifice ends Salem's hysteria.