Changling: I just want to point out that all of the major religions - such Christianity; Islam; Judaism; and Hinduism - all contain a "strain" or a "thread" of thought that is usually labeled as "materialist." Moreover, it is also often assigned the epithet "heretical," and is often surpressed.
Materialism is an ancient mode of thought, and can be found in all the "Classical" civilizations. For example, in the Indian civilization, the materialist doctrine, Lokayata, was in "full bloom" in the seventh century B.C.E. In classical Greek thought, the philosophies of Democritus and Heraclitus are usually termed "materialist."
It basically all comes down to this question: Do humans possess any sort of "spirit" or "soul" that persists or continues on after the death of the body? The materialist response [in all traditions, throughout the world] is a resounding "No!" According to materialist doctrine, the human "spirit" or "soul" perishes at the time of death of the human organism."
I should emphasize that philosophical materialism is an ancient idea, found in all cultures and religions. As I pointed out in a previous post, Judaic materialism is especially prevalent in Ecclesiastes where the writer says outright that there is no life after death. This makes him the "odd man out" in the Bible, but any honest reader will at least have to "engage" him and ponder what it is that he has to say.
Although materialism often accompanies atheism; they are not necessarily the same idea. Whereas, I suppose, that most atheists would espouse materialism, not all materialists are necessarily atheists [although many are.] The reason for this is because the question of whether or not the human soul survives death is quite different from the question of whether God exists [or gods exist]. The two questions are totally independent of each other.
Materialsm is often associated with the philosophical poition of doubt. Again, the two are not synonomous or co-equal, but materialsm will often lead to skepticism. Doubt is NOT the shadow, or "poor sister," of belief. Doubt and skepticism are not mere reactions against belief. Doubt is sufficient unto itself. It has its own methods and its own theories. Doubt need not exist in antagonistic relationship to belief. In fact, sometimes doubt can butress and fortify belief.
I am currently reading a book entitiled Doubt - A History, by Jennifer M. Hecht. In her book, she traces the development of skepticism as it is usually accompanied my materialist thinking. I was shocked to read about such an ancient lineage. It seems like the older the religious tradition, the older the materialst tradition that deneid it. It astounding to read that thousands and thousands of years ago, there were people who scoffed at the foundational concepts of Hinduism such as reincarnation and karma. These people, called the Carvaka, claimed that those who believed in the afterlife were fools and simpletons. And these Caravaka were not the only one, or the first.
It seems that every major religion is based on the foundational premise that there exists some supramaterial, immortal soul, and that this "soul" is to face either reward or punishment in the afterworld. What surprised me is that there have always been people - in all religious traditions - who have offered rationalist proofs denying the very existence of this "immortal soul." These people have always been there. They have often been in the background, due to suppression by the orthodoxy of their respective religious traditions. More often than not, scholars know about them only through the writings of their enemies, those who denounced them. This is an irony that often occurs in history. There will be a group or a "school" of thought, none of whose original writing survive, due usually to the fact that they were burned ["they referring basically to the writings, but sometimes to the people who wrote them]. Their writings survive only as incorporations into the counter-writings of their enemies. It was often the case that the orthodoxy of the various religious traditions would copy copiously the writings of materialists.
