Hence, we are justified in rejecting scientific conclusions whenever they bear on matters of the spirit. A causes another thing B is to say that anytime A occurs, B must occur as well. Some people claim that cigarette smoking causes lung cancer. This is obviously not true. Experiments on human beings have repeatedly shown that the majority of people who smoke don't get lung cancer.
Science is fundamentally a social institution governed by power relationships.
When scientific consensus exists, it is because a particular group of scientists is in power. There are always scientists who disagree with the consensus, but they are marginalized, and their views are silenced by the ruling group. When a scientific revolution occurs, it is not because some great new discovery has been made, but rather because the group in power has been somehow overthrown. Hence, the whole idea of scientific progress is a myth.