I think this is a common fallacy that the religious have when they think of the non-religious: they think that because they have a god or gods they believe in, somehow those that don't believe in supernatural agency in the universe are without any "spiritual" sense. This is an understandable assumption since the term "spriritual" has the root of "spirit," at supernatural/paranormal entity in many definitions. But it also holds the definition of the driving force and motivation among people:
team spirit in sports and competition;
esprit de corps among those same sports teams or in a military unit or any team that has a common purpose; and the
spirit of wonder and awe that envelopes youngsters as they discover the world around them.
One need not be deluded by a religious doctrine to be spiritual. One need only not be satisfied or content with what is known. I find many atheists to be far more spiritual than many theists
because they're skeptical and not willing to settle on magical answers like "god did it."
Richard Feynman, physicist and atheist, once wrote a poem that included:
There are the rushing waves
mountains of molecules
each stupidly minding its own business
trillions apart
yet forming white surf in unison
[...]
Out of the cradle
onto dry land
here it is
standing:
atoms with consciousness;
matter with curiosity.
The full poem can be found
here, along with links to others.
And it was Carl Sagan, astronomer and atheist, who commented "
There is a place with four suns in the sky — red, white, blue and yellow; two of them are so close together that they touch, and starstuff flows between them. I know of a world with a million moons. I know of a sun the size of the Earth — and made of diamond. There are stars leaving the Milky Way Galaxy... there are perhaps, places outside our universe. The universe is vast and awesome, and for the first time we are becoming part of it. No longer does 'the world' mean 'the universe'. We live on one world among an immensity of others. The cosmos revealed to us by the new advances in astronomy and biology is far grander and more awesome than the tidy world of our ancestors."
It doesn't take a belief in a magical being to have a spiritual sense. One need not believe that magic was at work to be in awe of nature. Nor does one need adhere to superstitious doctrine in order to be completely awestruck by the sheer number of particles in the universe, that we are made of those same particles that stars are formed of, and still allow oneself to be in love, regardless of whether its understood to be a trick of evolution to ensure that one's DNA is propagated and protected. The "star-stuff" I'm hopelessly in love with just turned five yesterday and I don't need to think that it's a supernatural cause that gives her 23 of my chromosomes and 23 of those that belong to the other collection of "star-stuff" I'm in love with.
And I truly feel sorry for those that need supernatural explanations to satisfy them; those who cannot allow themselves to simply be in awe and wonder about that which is mysterious or even relatively explainable.