Science is a faith
Science is a faith is a statement that reflects a straw man or equivocation fallacy propagated by apologists to attempt to discredit "belief" in science as being no more sound than belief in God. Science does contain philosophical underpinnings which are unprovable, which thus require "faith" in the epistemological sense. However, science distinguishes itself from purely faith-based beliefs in the same way that philosophy does; by the application of logic. Science also goes one step further by adhering to demonstrable, repeatable experiments and empirical data.
Furthermore, the statement indirectly generates a false dilemma by positioning science as "the dogma of the atheist" and as a tool to attack religious believers. Science is neither the dogma of the atheist nor a tool to attack theists; two examples that illustrate this are an individual who does not believe in god but performs a daily ritual to summon good luck, and an individual who does believe in God yet nonetheless follows the scientific method in his or her research. Science simply is not synonymous with atheism.
Development of Scientific "Beliefs"
Most respected scientific papers, which introduce new concepts into widespread discussion, are peer-reviewed. Peer review is the process by which scientists in the relevant field are tasked with judging the study detailed in the paper for soundness of experimental design, data analysis, and conclusions. A critical requirement for a paper to pass peer-review is that the study must be described such that it can be replicated easily by a scientist wishing to subject the conclusions to another test. In this way, other scientists can either repeat or challenge the work that produced controversial findings. Over time, scientists can amass evidence, confirm hypotheses, and eventually refine theories. Claims that scientists make, therefore, are necessarily supported by developed systems of logic and reason applied to available evidence. Anyone with the resources to replicate an experiment or the intellectual capacity to critique conclusions is free to do so. This leads to a continual challenging of the status quo and the development of a more complete and nuanced understanding of our world. Faith is not a tool of science, as faith does not promote greater understanding of the world in this same way.
The value of inquiry without faith can be demonstrated easily in the modern world. The reliable performance of so many of our modern technological conveniences depends on the repeatability of scientific findings. For example, modern telecommunications technologies, which use the exchange of "packets" of encoded information over a multitude of media from wireless technology to fiber optics, is able to relay complex information thousands of miles around the world in a way that can be decoded by a recipient within seconds. The rapid delivery and high fidelity of such data are not dependent upon faith but upon repeatable phenomena discovered and manipulated using a rigorous, evidence-based approach. Is a cell phone powered by faith? Of course not!
Religious beliefs generally are maintained solely on the basis of faith. For example, the Christian evangelical who promises a potential convert a paradise after death has no means to demonstrate his or her claims, and is simply banking on the goodwill and faith of his or her target. Such faith is unhelpful in discerning what is true about the world. The faith that leads to growing numbers of evangelicals is not demonstrably different from the faith that leads to the growth of Mormonism, Islam, or any of a number of other religions.
Can faith, as a means of knowledge-seeking, be demonstrated to reveal truths about the world? No, of course not; whether the beliefs of the faithful are likely to be correct depends not on the rigor or quality of his or her faith. In contrast, scientific inquiry reveals many more truths about the world than the faith of any believer. Whether the evidence-based beliefs of an investigator are correct depends on the rigor or quality of the evidence available. This difference in approach leads to a striking juxtaposition in effectiveness for these alternative means of developing beliefs. The difference in efficacy between faith and scientific inquiry is trivial to demonstrate--just point to the advances in knowledge and technology of the past century!