"The map is not the territory."

Map–territory relation - Wikipedia, the free encyclopedia:

"The map is not the territory is a remark by Polish-American scientist and philosopher Alfred Korzybski, encapsulating his view that an abstraction derived from something, or a reaction to it, is not the thing itself. For example, the pain from a stone falling on your foot is not the stone; one's opinion of a politician, favorable or unfavorable, is not that person; and so on. A specific abstraction or reaction does not capture all facets of its source — e.g. the pain in your foot does not convey the internal structure of the stone, you don't know everything that is going on in the life of a politician, etc. — and thus may limit an individual's understanding and cognitive abilities unless the two are distinguished. Korzybski held that many people do confuse maps with territories, in this sense."

We find this confusion a hell of a lot today, especially in politics.