Context: To Popper, who was an anti-justificationist, traditional philosophy is misled by the false principle of sufficient reason. He thinks that no assumption can ever be or needs ever to be justified, so a lack of justification is not a justification for doubt. Instead, theories should be tested and scrutinised. It is not the goal to bless theories with claims of certainty or justification, but to eliminate errors in them. He writes, "there are no such things as good positive reasons; nor do we need such things [...] But [philosophers] obviously cannot quite bring [themselves] to believe that this is my opinion, let alone that it is right" (The Philosophy of Karl Popper, p. 1043)

Question: According to Popper, what is not grounds for doubt?
Answer: lack of justification

Question: What principle of traditional philosophy did Popper take an anti-justificationist stance against?
Answer: principle of sufficient reason

Question: What does Popper believe is essential to do to theories instead of justification?
Answer: eliminate errors

Question: What don't we need to look for about theories in Popper's view?
Answer: good positive reasons

Question: Who was a pro-justificationist?
Answer: Unanswerable

Question: What did Popper think needed to be justified?
Answer: Unanswerable

Question: What is a justification for doubt?
Answer: Unanswerable

Question: Who believed that good positive reasons exist?
Answer: Unanswerable

Question: What did Popper think should never be tested or scrutinized?
Answer: Unanswerable