Three years ago I wrote a book titled, Reflections On the Existence of God. It proved to be very popular in part, I believe, because it was easy to read and understand.

One of the primary themes of the book is the issue of intellectual integrity. After years of research I came away with a frequent observation of the contradictory nature of atheism. It is very easy to claim to be an atheist, it is hard to live as if it were true. The contradiction is generally a tension between logic and life.

Many atheists who have true intellectual integrity often change their minds. They recognize the contradictory nature of their atheistic worldview and, being honest people, conclude that it isn’t livable.

Recently I read of another individual who began to wonder whether his atheistic views really fit the actual world he lived in. It comes from the best-selling book, When Breath Becomes Air, which is the reflections of a young neurosurgeon. He writes about his journey back towards faith in God while he was battling cancer.

Paul Kalanithi had been an “ironclad atheist.” His primary charge against Christianity was “its failure on empirical grounds. Surely enlightened reason offered a more coherent cosmos . . . a material conception of reality, an ultimately scientific worldview.” But the problem with this whole conception became evident to him. If everything has to have a scientific explanation and proof, then this “is to banish not only God from the world but also love, hate, meaning— . . . world that is self-evidently not the world we live in.”

All science can do, Kalanithi argues, is “reduce phenomena into manageable units.” It can make “claims about matter and energy” but about nothing else. For example, science can explain love and meaning as chemical responses in your brain that helped your ancestors survive. But if we assert, which virtually everyone does, that love, meaning, and morals do not merely feel real but actually are so—science cannot support that. So, he concluded, “scientific knowledge [is] inapplicable” to the “central aspects of human life” including hope, love, beauty, honor, suffering, and virtue.

When Kalanithi realized that there was no scientific proof for the reality of meaning and virtue, things he was sure existed, it made him rethink his whole view of life. If the premise of secularism led to conclusions he knew were not true—namely that love, meaning, and morals are illusions—then it was time to change his premise. He found it no longer unreasonable to believe in God. He came to a belief not only in God but also in “the central values of Christianity—sacrifice, redemption, forgiveness—because I found them so compelling.” Paul Kalanithi had also found that, the completely secular point of view had too many things “missing” that he knew were both necessary and real.

It is very difficult to live with a worldview that cannot rationally explain everyday life. It only seems logical that if your worldview does not work out in the real world, there must be something wrong with it. Nancy Pearcey says a good way to evaluate a worldview is to submit it to a very practical test: “Can we live by it?” Does it fit what we experience in life?

This reminds me of the great British philosopher C.E.M. Joad, who was agnostic most of his life. Later in life, he became a Christian and wrote a book on his spiritual experience titled The Recovery of Belief, which was published a year before he died. What was interesting is the reason he gave for this decision. He said it was a result of intellectual observation. After studying all the issues and all the evidence it became apparent to him that the Christian theistic view of life covered more of the facts of experience than any other. Therefore, he said, “I have been gradually led to embrace it.”

Richard E Simmons III is the founder and Executive Director of The Center for Executive Leadership and a best-selling author.