Common sense (or, when used attributively as an adjective, commonsense, common-sense, or commonsensical), based on a strict construction of the term, is what people in common would agree: that which they "sense" in common as their common natural understanding. Some use the phrase to refer to beliefs or propositions that in their opinion they consider would in most people's experience be prudent and of sound judgment, without dependence upon esoteric knowledge or study or research, but based upon what is believed to be knowledge held by people "in common", so: the knowledge and experience most people have, or are believed to have by the person using the term. Whatever definition is considered apt, identifying particular items of knowledge that are "common sense" is more difficult. Philosophers may choose to avoid using the phrase where precise language is required. Common sense is a perennial topic in epistemology a