In 1841 a little-known English poet escaped an asylum and wandered back to his childhood home in the farmland of Northamtonshire, convinced that he was married to a woman who had died three years earlier.

The poet, John Clare, said that separation from his childhood home–its fields, cottages, and the small taverns where he worked–had made him increasingly alienated from his own self. His later poems reflect his fixation. In one he claims that he was once Shelly and Lord Byron. In his most famous one, “I Am,” he reflects on his isolation:

I am—yet what I am none cares or knows;

My friends forsake me like a memory lost:

I am the self-consumer of my woes—

They rise and vanish in oblivious host,

Like shadows in love’s frenzied stifled throes

And yet I am, and live—like vapours tossed.

Isolated and unknown, Clare clings to the few activities, memories, and passions that adhere to his fragmented self. This raises an important question: Who is this “I Am” Clare speaks of, separated from his roots? Who is an I? What is a self?

At the most basic level, “self” is considered to be a definitive something that distinguishes you from other people. It’s an essence of identity. It’s what makes you you.

Probably the must fundamental view of self would be the idea of “substance” self. Here, the self is an actual “substance,” not a list of qualities. The easiest example of this would be the soul, especially the Greek notion.

For Plato and Socrates, the soul contained the mind, the collection of cognitive elements–consciousness, memory, thought–that gives us awareness and lets us process our surroundings. Must of us associate mind with our brains. For Plato and Socrates, however, this wasn’t the case. For them, mind was part of soul, which was separate from body. In fact, soul wasn’t material at all.

For them, the body dies, since all physical things die, but the soul lives on, carrying our mind into the afterlife. As Socrates’ argues in the Phaedo, “when death comes to man, the mortal part of him dies, it seems, but his deathless part goes away safe and indestructible, yielding the place to death.”

Thus, the body really doesn’t mean anything to us. In one argument, Socrates compares it to an old piece of clothing that we replace with another. For him, self is all about soul.

This notion leads to much of the mind-body dualism we have in our culture. René Descartes, French philosopher and mathematician, cemented the Greek dualism in the 1600s with his famous Meditations. After doubting all of his senses and thoughts, he concluded the only thing that he could not doubt was his own doubting, leading to his famous dictum “Cogito Ergo Sum” ‘I think, therefore I am.’

Descartes, like Socrates and Plato, thought our essence resided in our mind because our own consciousness is the most immediate experience we have. Everything else–including the itches on our own skin–feels outside of this consciousness. Like a child in a Halloween mask, we peer through eyeholes at the world around us, but the real “self” is the experience of mind we can’t get out of.

And whether it’s through cultural conditioning, intuition, or experience, most of us have a similar outlook: Our self closely connects with our mind, which somehow differs from our “body.”

However, not everyone agreed with this view. At the opposite end is the “bundle theory” of self, described by Scottish philosopher David Hume, born in 1711. A near contemporary of Descartes, Hume was from the opposing school of thought: empiricism. While Descartes thought that the mind was primary, Hume celebrated the senses. They give us the experiences that become thoughts. Without them, minds would be a boring place.

For example, Hume compared the thought of a fire to the real thing. On a cold winters’ day, struggling across some bleak Scottish heath, one thinks of a hearth crackling and dancing away behind an old grill. There, in the midst of the cold, we recall heat. We may even “feel” the heat and hear the logs pop. But, says Hume, the thought of the fire comes from the original experience. No real fire, no thought of fire. Moreover, the actual experience of fire is more intense.

Likewise, Hume viewed the self as a bundle of experience, abstracted somewhat into properties. If someone asked you to describe yourself, you’d name a series of traits. Perhaps you’re funny, or shy, or a spot on snooker player. Each of these represents experiences. You can’t be shy unless you experience shyness. You may even use a story to describe this–a story, again, of an experience. Try to define your self, and you have a hard time naming anything beyond properties.

Thus, Hume didn’t think there was an underlying substance to our self because we can’t actually experience any substance. We can only experience these properties. Our thoughts, memories, recurrent life patterns, and names may give us a false sense of self, but peel away the layers–like an onion–and you’re left with skins reflecting experience after experience. Nothing more.

The Buddha had a similar idea.

According to the original Pali texts that ground Buddhism, the Buddha said that the self is just an illusion we create to sort through a variety of combining elements called skandhas or “aggregates.” We cling to this self regardless, holding it together as karma tugs us through death and rebirth. Christopher Gowans, a philosopher at Fordham, stresses the similarity with Hume: in both cases, a theory of persistent selfhood–an actual self that endures through time–is illusion.

The Buddha himself was working from a Hindu background, where the self, or “atman,” is a somewhat illusory expression of “Brahman,” the transcendent reality that grounds everything. We make think we’re all separate, but we’re just different expressions of the same thing–like shards of the same fractured glass. In Hinduism, an Enlightened person sees this.

Gottfried Leibniz, a contemporary of Descartes, called this view of reality philosophia perennis or “perennial philosophy.”

As time went on, the idea of self grew more complex as people considered its social layers. One of the most interesting notions comes from German philosopher G.F. Hegel in 18th to 19th centuries. For him, the self–which he associated with the term particular–can only makes sense in light of the universal, the collective whole of everything. The particular understands itself based on the the ideas and processes of the universal. Moreover the self’s “subjective will” should bend to the will of the universal, which truly pushes and moves history through states, cultures, and significant people.

For Hegel, our little lives don’t mean much in themselves. They gain meaning through their participation in the universal.

My personal favorite notion of self arises in existential thought. Jean Paul Sartre, one of the few existentialists who actually accepted the title, allegedly said, “We are our choices.” I’ve had a hard time tracking down the actual  source of his quotation, but it sums up his philosophy quite well anyway.

Sartre means that our actions define us. We must chose what we wish to become and express our choices through actions. These actions can come from our own decision and sense of “authenticity,” or they can come from what society tells us to do. The authentic person accepts the responsibility–and all the “anguish” and “forlornness” that comes from this–and choses his or her destiny.

For example, I could either become a corporate executive because I have a passion for it, or I could let my parents, school administration, and peers steer me in that direction because that’s a sensible thing to do. Much more sensible than studying philosophy, anyway. Moreover, as a corporate executive, I could simply recycle the stereotypes and labels that already exist or take hold of those labels and change them by my own choices.

German philosopher Martin Heidegger (1889-1976), whose early work was a major influence on Sartre’s, said that the self we first encounter is the “they self,” they (Das Man in the original) standing in for the society and culture that has already pre-interpreted our world and all the meaningful relationships in it. We value what we value and think what we think because they say we should.  Authentic people for Heidegger, like Sartre, choose and own their choices, making their own interpretations. They don’t simply so with the herd. Even if they do what everyone in the heard is doing, they’re aware of it.

This brief spattering only skims the bare surface of the self. Each of these views has much more depth and implications, and I haven’t mentioned hundreds–perhaps thousands–of other thinkers, artists, and scientists.

And, in my opinion, we live in a culture obsessed by the I. We layer it with titles and qualifications, we surround it with stuff, we immerse it with social relationships–some face to face, others through social media and telephone–and we spend our whole lives trying to express that self. The clothes we wear, the products we purchase, and the words we use work like a well-crafted marketing campaign. But we’re not selling a product. We’re selling ourselves.

We’re trying to make our beliefs intelligible, even desirable, to the people around us. Even notions of counter-culture–a violent assertion of self against the norm–often operate according to common symbols and social norms that an individual takes on or takes part in.

Despite our best efforts, the “I” is always part of the “we.”

And perhaps this isn’t a bad thing. We’re social animals, after all. But I often wonder what lies buried beneath all this clutter. Are we simply the accrued layers of what we use to express and make sense of ourselves? Are we our thoughts? Some non-dualist union of mind and body? An expression of metaphysical, transcendent union? I don’t know. But we have a lifetime to explore this, and perhaps that’s what life is all about: getting to know your self and the world around you–if there’s even a difference at all.

And thus, like Clare, “I am and live.”