When you warm a house, you also warm the people inside.
If a house burns down, the people inside burn too.
If you damage a house, the people who own it pay.
Ergo, houses ARE people. Clearly.
Corporations are legal structure. A house is a physical structure. Corporations bring capital together in a common purpose and shelter individuals from liability. Houses bring people together in a home and shelter us from the elements.
Of course what we do to a corporation affects the people involved in the corporation. That is true of virtually anything in this world. But, the reality is that we recognize that vessels and structures are not, in and of themselves, people.
It would be possible to simply say that taxes on corporations are paid by people. It is similar to the argument advanced for years that taxes on merchants are paid by customers. That argument never needed to become a claim that "merchants are customers." But, the "corporations are people" argument must go further. It is because this assertion is not a simple analogy for the purposes of election politics, it is about extending to corporations fundamental rights granted to people under the law.
It isn't the same as arguing that I can put a political poster on my house because I have a right to political speech. It is saying that the house itself possesses this right. It's a fine, but highly dangerous distinction. It is a distinction that allows corporations to speak and act with the rights of a person, but keeps the wealthy individuals behind the corporation's walls sheltered and separate. It is a distinction that is not missed by highly educated, very wealthy individuals like Romney.