[avivo]

There is a critical difference between most corporations and people, which makes them far more dangerous - for a corporation the "only" goal is profit. In colloquial terms, corporations are "psychopaths".

Corporations being psychopathic can be very useful for a number of applications (such as efficient resource allocation and rapid economic growth), especially given a regulatory system that ensures that the pursuit of profit provides utility to the commons. It's so useful, that we even require corporations by law to single-mindedly pursue profit - if they didn't, and e.g. your social security benefits were invested in those corporations, there would be no recourse if they spent their money negligently.

Unfortunately, when corporations amass enough power to control the regulatory system you have major issues, as there is nothing to control their "psycopathic" tendencies. This is a crucial reason why "corporate personhood" and other forms of corporate power should have limits - in order to keep our checks and balances functioning. If we fail to do this, profit maximizing entities will gain more and more control over the resources available to human beings.

So, while many aspects of corporate personhood are wonderful and convenient, we need to be very careful what powers corporations are granted.

[yes, I gloss over some details to keep this short: fiduciary duty conditions, clinical definition of psychopathy,..; but these don't critically affect the main thesis as far as I am aware]