The mind is the way we define ourselves, what it means to be us. A survey of more than 2,000 people by psychologists at Harvard University reveals how we perceive the minds of others and what criteria we use.

The survey found that we use two dimensions by which we perceive the minds of others: agency and experience. Agency means the ability for self-control, morality and planning. Experience represents the capacity to feel sensations such as hunger, fear and pain.

Respondents to the survey were presented with 13 characters: 7 living human forms (7-week-old fetus, 5-month-old infant, 5-year-old girl, adult woman, adult man, man in a persistent vegetative state, and the respondent himself or herself), 3 non-human animals (frog, family dog, and wild chimpanzee), a dead woman, God, and a sociable robot.

The respondents were asked to rate each on the possession of characteristics of agency and experience. The results may give insight to how moral and philosphical questions are individually answered as well the formation of a society’s views on issues such as capital punishment, abortion and torture.

The fetus was regarded as having experience but no agency. The man in a persistent vegetative state scored low on agency but in the middle range on experience, showing that people may disagree on whether he would be capable of experiencing sensations.

“The perception of experience to these characters is important, because along with experience comes a suite of inalienable rights, the most important of which is the right to life,” co-author of the study, Kurt Gray says. “If you see a man in a persistent vegetative state as having feelings, it feels wrong to pull the plug on him, whereas if he is just a lump of firing neurons, we have less compunction at freeing up his hospital bed.”

Respondents viewed themselves as highest in agency and experience and viewed the normal man and woman to possess the same degree of these attributes.

How we view the minds of others shapes how we relate and how we believe society should relate to and treat them. If we believe a person has agency - that is, can tell right from wrong and possesses self-control - then society may punish them for wrong-doing. It is when we believe that they may not possess full agency, say due to mental illness, that our response to their actions is altered.

The findings of the study are published in the journal Science.