Tonight I came across the following in Ayn Rand: A Sense of Life: The Companion Book:
You see, I am an atheist and I have only one religion: the sublime in human nature. There is nothing to approach the sanctity of the highest type of man possible, and there is nothing that gives me the same reverent feeling, the feeling when one's spirit wants to kneel, bare-headed. Do not call it hero-worship, because it is more than that.
If a life can have a 'theme song' -- and I believe every worthwhile one has -- mine is a religion, an obsession or a mania -- or all of these -- expressed in one word: Individualism.
Ayn Rand is clearly using the term "religion" in both of these quotes in the non-supernatural context. Similarly, her usage of the term "spirit" here, and "soul" elsewhere, to mean mind is not incompatible with her naturalistic worldview. When she refers to the "sublime", the "sanctity", and a "reverent feeling", we may assume she is speaking of experiences appropriately defined with a spiritual terminology.
A few days ago I finished reading a history of the founding fathers of Religious Humanism, the hard-to-find book American Religious Humanism by Mason Olds. Before I read this book, I used to think that the early Humanists were socialists. I read, however, that like the founder of Ethical Culture, they rejected both socialism and communism as incompatible with individualism. There was, however, at least one of the Humanist pioneers who was an advocate of what we now frequently label as "socialism" but is more correctly described as the welfare state.
If only atheism were more commonly associated with capitalism rather than communism! In the Optihumanist Principles, I explicitly distance my own flavor of Religious Humanism from any association with socialism or the welfare state. It is because I, too, hold Individualism to be my religion.