For most of the history of Western civilization, the concept of spiritual enlightenment was virtually unknown to Westerners. Spirituality was primarily confined to Judeo-Christian religious institutions, where authority figures in charge of churches and synagogues indoctrinated individuals about “proper” behavior and the “proper” worldview. Only to a few intellectually and spiritually adventurous Westerners, such as William Blake and the American transcendentalists in the 19th century, were willing to look Eastward, beyond the institutional dogma of the West.

Then, with the counterculture movement of the 1960s, all of that began to change. As cultural authority and traditions were questioned and uprooted, religions from the East, such as Buddhism, Hinduism, and Taoism, began to influence spirituality in the West. As we moved into the 21st century, words like “aura,” “guru,” and “yoga” had all become part of common parlance.

And the word “enlightenment” — used in the spiritual sense — is now bandied about with ease, being applied to politics and products as often as it is to actual spiritual practice. Now, we have a popular TV show and a computer program named “Enlightenment,” a line of snack foods called “Enlighten,” and TV ads and other advertisements that play off New Age paths to enlightenment.

The problem with that, of course, is that the deeper meaning of the concept becomes cloudy, and the sacredness of it gives way to the profane. So, what then is enlightenment, in the purer spiritual, esoteric sense? What exactly is being “lightened,” and what is going on within the individual when enlightenment occurs?

The precise definition of enlightenment is elusive since real understanding can only come through direct experience of it. But many teachers have done their best to provide an explanation, which varies greatly among disciplines. Perhaps Lao Tzu offered the simplest definition of enlightenment when he wrote in the Tao Te Ching, “Knowing others is wisdom. Knowing yourself is enlightenment.”

This statement reflects one aspect of achieving enlightenment about which all Eastern practices agree: enlightenment always involves some fundamental shift in self-concept. Enlightenment is not about knowing how to live a good life or about knowing religious precepts. Rather, it means letting go of one’s false, worldly identity in favor of a truer, deeper perception of self.

Many spiritual teachers narrow this down to the fundamental struggle between ego, the sense of individual identity gained through socialization, and the “true self” or the soul, the self that transcends the limitations of the earthly body. The ego is problematic because, as Buddhist monk Matthieu Ricard states, it engenders “ … a distorted vision of reality that makes us think that what we see around us is permanent and solid, or that our ‘self’ is a real, autonomous entity. This leads us to mistake fleeting pleasures or the alleviation of pain for lasting happiness. Such ignorance also makes us attempt to build our happiness on others’ misery.”

Thus, ego is at the root of human suffering, and overcoming the ego, both individually and collectively, is the key to lasting peace and happiness.

Although the process of enlightenment ultimately leads to a blissful state that is free of suffering and desire, getting there is not a painless process — one that many teachers compare to dying. Transpersonal psychologist Stanislav Grof described it this way: “There is no fundamental difference between the preparation for death and the practice of dying, and spiritual practice leading to enlightenment.” Enlightenment is a “death” because all the many attachments of the ego must be surrendered and released, as inevitably happens to all of us upon physical death.

For a few, dropping the ego happens instantaneously, but for most this is excruciating because becoming enlightened undermines everything the ego holds dear: personal pride, social status, financial wealth, individual accomplishment, and so on. The self that is left over is the self that exists beyond the confines of the physical body, an essence that continues beyond time and space. It is a self that has no separateness from the rest of the universe, and thus is not subject to the weaknesses and desires that come with a life focused on the physical body.