Definition: The answer will be 'yes' if the provided sentence contains an explicit mention that answers the given question. Otherwise, the answer should be 'no'. Instances where the answer is implied from the sentence using "instinct" or "common sense" (as opposed to being written explicitly in the sentence) should be labeled as 'no'.
Input: Sentence: Durer rejected Alberti's concept of an objective beauty, proposing a relativist notion of beauty based on variety. 
Question: How often are philosophical concepts rejected?

No.