We are the masters of our own domains, the kings and queens of the castle. We are the one in the driver’s seat and the one who pulls the strings and calls the shots. That is, until our stomachs start to growl.

New research suggests how much agency we believe we have is determined in large part by physiological behaviors. The world is ours for the taking — until we have to pee. We write our own lives, unless we are aroused or feel a little sluggish. In these moments of brief surrender to bodily functions, science is finding, how we view our sense of control goes through changes. We believe more in fate and less in ourselves.

"Others have assumed that beliefs about free will are shaped by religious and political doctrines and logical reasoning," explained psychology researchers Michael Ent and Dr. Roy Baumeister, of Florida State University, authors of a new study on the subject. "Yet such beliefs are at least influenced by bodily cues as seemingly innocuous as a full bladder or an unfulfilled desire for sex."

The Cheeseburger of Fate

At the heart of the research is a theory in philosophy known as embodied cognition. It asserts the brain actually isn’t the master. It, too, is subject to outside forces. Physical changes like sensations of hunger or sexual arousal affect how the brain works to the extent that it can change a person’s metaphysical perception. Stripped of all its jargon, embodied cognition says the body influences the mind; the two aren’t toiling away in separate offices.

Ent and Baumeister wanted to explore this idea even further to see if people’s attitudes about themselves and the world could be shaped in the presence of changing physiologic states. Could your entire sense of destiny be changed, all because your stomach was empty and you wanted a cheeseburger?

To answer this question, or at least approach some semblance of understanding, the research team conducted a set of surveys. The first asked a group of people with epilepsy or panic disorder whether they felt a sense of free will, and it asked the same question to a group of healthy-minded people. The people with epilepsy or panic disorder reported they felt like they had less free will overall — the first piece of evidence that physical disorder may alter a person’s philosophical lens.

Later, Ent and Baumeister asked a group of 81 people to rate their current state of needing to urinate, have sex, go to sleep, or eat. Those who experienced these sensations more were also more likely to answer in the same vein as those with epilepsy and panic disorder: They felt less control over their own lives. There was one exception, however. In this second survey, hunger didn’t show the same effect as the other feelings. So the team enlisted 112 more people to delve deeper into the issue.

What they found in their third survey was that if they asked people about their sensations of hunger and whether they were also on a diet, the small lifestyle change ended up making a world of difference. When they removed the hungry dieters from the data, the effect bubbled back up — presumably because dieting is an active process that involves a measure of planned suffering, and any hunger people feel is because of their own doing.

“Embodiment may be a more far-reaching phenomenon than previous research has demonstrated,” Ent and Baumeister concluded.

Such prior research has upheld the effects of physical changes on subjective perceptions, but none insofar as the big notions of pre-destination. Harvard psychologist Amy Cuddy found, for instance, that assuming a hands-on-hips Wonder Woman pose can release a surge of adrenaline, cut cortisol levels, which eases your stress, and boost a person’s confidence. We smile when we’re happy, but smiling also makes us happy. Warmer rooms make us feel closer to people.

In Fate’s Greasy Hands

Ent and Baumeister’s research has its limits. As a collection of surveys, it can’t make any experimental claims that physiological changes, in isolation, caused these feelings of free will. It could be the case that people who feel less in control of their lives are more prone to succumb to their bodily sensations. (Although, no matter how fearless babies may seem they inevitably succumb to certain bodily sensations.) The research also can’t set strict parameters for what “hungry” or “aroused” feel like in terms that can be measured, so the levels may differ.

More research is needed to understand the precise effects these feelings have on people’s perception of free will, but in the meantime it’s probably safe to assume the hungrier you are, the less free will you feel. You can’t feel guilty about stuffing your face if it was your destiny all along.

Source: Ent M, Baumeister R. Embodied free will beliefs: Some effects of physical states on metaphysical opinions. Consciousness and Cognition. 2014.