> Imagine I could read your mind by reading someone else mind. are you ok with me having access to your private thoughts just because someone gave me access to

> Imagine I could read your mind by reading someone else mind. are you ok with me having access to your private thoughts just because someone gave me access to their mind? Even if you and I were parent and child, I don't think there's a reasonable philosophy of ownership on which you could hinge the notion that I can't donate the DNA in my cells to a cause because the pattern of half of the (physically completely independent) DNA in your body has a relationship to my own. I do think you're touching upon possibly an interesting wrinkle in the way our current philosophy of ownership treats data about groups vs. data about an individual. Similar lines of thought underpin the question of whether your friends are culpable for sending data about themselves to Cambridge Analytica if it allows CA to extrapolate information about you. However, I currently know of no philosophy of ownership that makes the described scenario bad apart from the general "it's a dick move if you do it on purpose to screw someone else over" (but that hinges on the general category of "Don't screw people over on purpose," not on any concept of joint ownership of data). To pull another analogy: imagine I had dated a rapist and although I didn't have enough evidence to get him convicted of a crime, I told all my friends he was dangerous and now they won't date him. Is this bad? Quite the opposite; it's the system that is already of necessity in place to protect people from bad actors that the legal system fails to handle.