You enter the cave, walk through tight spots, crawl on hands and knees and come out, 100 yards later, into a dark room, a widening in the cavern walls, and see, if you point your lamp at them, some of the most beautiful animals ever drawn by human hand.

The very first art — some 30,000 years old — is some of the best, and what you have are pictures of animals. On the walls at Lascaux, Chauvet and Altamira in Europe, you find bison and elk, aurochs and rhinoceroses. When you find people drawn on the cave walls, they are hardly more than stick figures, but the animals are often so realistic you can identify them by genus and species.

You can see it in the Egyptian tomb paintings, too. Human figures are stiff, in the artificial “King Tut” poses so familiar from the hieroglyphs. The humans are stylized and symbolic rather than naturalistic. But the animals don’t share that fate: They are seen with a grace and directness at odds with all the machinery of symbolic hieroglyphs — a real duck, a real hippopotamus, a real ibis.

You can see it too at the Palace of Minos in Knossos, where the mural is filled with graceful dolphins and mackerel.

Or in the mosaics at Pompeii, with its seafood menu of crustaceans, eels, octopuses and seabass. Animals have a special place in art.

They speak to us in a special language, even when they exist as a smaller part of another painting: the dog in Van Eyck’s Arnolfini Wedding, or the mink in Leonardo’s Lady With an Ermine.

It is an element that reflects us and we can’t seem to do without. But what is that element?

“They connect us to something larger or greater than ourselves, or with a past we’ve forgotten,” says painter Anne Coe, whose work is well known for its sometimes satiric use of animal imagery.

And, in fact, the animals in paintings almost always have an ulterior reason for being there. They are doors to something. “Something larger,” as Coe says.

But it’s a two-way door, and what the animals mean depends on your direction as you pass the portal.

Almost like choosing which end of the binoculars to look through, you get very different takes on what animals are and what they mean.

Going one way, the animals are symbols. They stand for all kinds of things: sometimes totemic, sometimes archetypal, sometimes they are as simple as elephants for Republicans and donkeys for Democrats. But they stand for something other than themselves. Perhaps the Democrats would be better symbolized by a platypus or the GOP by a warthog, but there you go: We are stuck with the symbols. Everyone understands them; they’re shorthand.

Medieval and Renaissance art is filled with this kind of symbology. The dog stood for faithfulness, the goat for lust, the lion for nobility. Of course, for the medieval mind, everything was a symbol.

We still have some of this emblematic symbolism with us: busy as a bee; crazy as a loon; the industrious ant vs. the lazy grasshopper. We tell Aesop fables to our children to warn them about bad behavior.

But going through the door in the other direction, the animals are steadfastly not symbolic, and force us to see them for themselves as separate entities in the universe. They force us to recognize them as “thou” in theologian Martin Buber’s formulation of “I-thou,” as distinguished from “I-it.”

You look at the eyes in a painting by animal portraitist May Cheney and you see the “there” there. There is no mistaking the cat or dog or goat for an insensible beast.

“An animal’s eyes have the power to speak a great language,” Buber himself said.

Cheney says, “The animal is present and looking back at you.”

And you are forced into the awareness that symbols are already several removes from reality, and that sometimes it is good to re-experience the world as it actually is.

When animals are symbolic, they are in some sense projections of ourselves. When they are not, they are reminders of all the rest of the universe. In either case, they kick-start us into the recognition of the larger connection we have with the world. And that is their function in art. After all, art itself is there to slap us into awareness, the way a doctor slaps a newborn into breath.

But whether the animals are symbolic or not, they also make us see them — as we come in the door or go out — either as kindred spirits, beings like us but in different form, or the opposite: beings that make us face the ineffable otherness of the world.

But there are more dichotomies, and more art to express them. Even if we see them as ourselves in fur or feathers, we have to ask: Are they similar to us because they are like us, or because we are like them? Are they people, too, or are we also animals?

“There is not an animal on the earth, nor a flying creature on two wings, but they are people like unto you,” it says in the Quran.

Western civilization has a long history of making a distinction between human and animal. The Bible gives us “dominion” over the beasts. We come up with all kinds of distinction to prove we are not animals. We have language, tools, laws, poetry. But looked at from the other side of the door, animals are no less distinct, no less deserving, no less intelligent than we are: Bees can make honey; humans don’t know how.

Mark Twain made fun of our presumed superiority to the animals: “I have been studying the traits and dispositions of the ‘lower animals’ (so called) and contrasting them with the traits and dispositions of man. I find the result humiliating to me.”

You can see these choices played out in art, and not only in European art. It is there in the manga drawings of Hokusai and book illustrations of Hiroshige, the temple carvings in India, the Mayan glyphs and in the Chi Wara antelope headdresses of Africa.

Animals mean something to all cultures. You can see it most directly in the paintings of children.

When they are introduced to animals in the classroom by a teacher who brings a bunny or a turtle, the children respond intensely. You don’t have to teach them anything about art: They burn to make paintings of the animals. You can’t stop them.

And their paintings in the first or third grades parallel the adult art, although in childhood terms: Sometimes they see themselves as the animal, playing baseball or caring for the animal babies, and sometimes they see the animals as something foreign, exotic and emotionally powerful. Boys, especially, love to paint sharks or dinosaurs.

The untutored and spontaneous identification with the animals is so deep that you can’t prevent it from happening. This may or may not be animals’ primary virtue, but it is one too often overlooked when we consider their value as pet, draft animal or cutlet.

They are there in all our art: The animals are either mirrors or windows. We look into the animals’ face and see.

Ultimately, the animals are a connection with the world: They allow us to deflate our species’ solipsism and recognize that connection.