Secular humanism might be described as the philosophical belief that all human beings have value and dignity, which is inherent rather than defined by supernatural beliefs or religious dogma.
A couple of interesting points about secular humanism-
-It shares a number of beliefs with traditional Christianity, especially the belief in the inherent worth and dignity of a human being.
-It provides no basis for that belief; no way of proving that humans do have any inherent value, other than their desire that it be so.
-Historically, it arose in areas (western Europe and America, specifically) with deep Christian roots.
I conclude that secular humanism is a Christian heresy; meaning a belief system which is a distortion of Christian belief. Secular humanism is an attempt to get the benefits of Christianity without paying the price, the price of submission to God. It is the belief that the blessings that have come to the world through Christianity can be enjoyed while rejecting the supernatural basis for those beliefs. It is a house built on sand, a philosophy with no epistemological foundation.
Even as secular humanists mock and deride Christianity, the fact is, that secular humanism could not exist without Christianity. It is like a parasite. It depends on a steady influx of people who accept the Christian belief in the inherent dignity of human beings. But since it rejects the basis for that belief (that man was created in the image of God), it cannot actually inculcate that belief itself. It can provide us with no reason why all human beings should have any particular worth, since in its philosophy we are all just matter. Why should one collection of organic matter be more important than another? Or why is organic matter of more inherent worth than non-organic matter? And why should I view people of different genders or races as of equal value? If Christianity were ever somehow to cease to exist, so would secular humanism, and the world would lapse back into barbarism and savagery. Fortunately, that cannot happen, as God is God and has promised that the gates of hell will not prevail against His church.
Secular humanism, therefore, is a great deal like the pagan attempts in late antiquity to stem the growing influence of Christianity by aping Christianity’s success. Julian the Apostate tried to encourage pagan temples to emulate the moral virtue and charity of the Christian clergy. He failed, because paganism lacks any real reason to do those things. Secular humanism will fail for the same reason; moral behavior and charity toward others can only really be grounded in the truth of a Creator that made us all in His image.