Science is as science does. Science is an attempt to understand the world as a purely materialistic entity. Although in and of itself science has no ideology it is generally driven by the intellectual descendants of the renaissance, who sought human dominion over everything else. For that reason many people treat science not as the tool that it is, but rather as the arbitrator of what is real and what isn't (see here).
Let's check Wikipedia, shall we? From its Scientific Method page: "To be termed scientific, a method of inquiry must be based on gathering observable, empirical and measurable evidence subject to specific principles of reasoning." Here is something interesting. Notice that the word "observable" is followed immediately by the word "empirical", even though the word "empirical" means "that which can be observed". Why this apparent redundancy? Is just incompetency with the english language? Not exactly...
The general method of science is to make observations, form a theory about them, test that theory by making further observations and changing the theory if need be. However, observations are based on our experiences of them, which opens the way to things like love, spiritual experiences, yearning and so on, which just doesn't seem "scientific" to the materialists. So they reduce what a person can observe through experience to the physical senses; sight, hearing, taste, smell and touch. Of these sight is the most important, followed by hearing, as it is for these senses that we have the most precise language. Hence, we begin to see the reason for the inclusion of the word "empirical", which can be taken to mean "observed by a large number of people".
Mind you, the Virgin of Guadalupe was observed by a large number of people so materialists dislike that definition also, so by "empirical" they mean "that which has been recorded by a machine". In doing this they are shirking their responsibility to understand the world by passing off all the detections thereof to a fairly sophisticated abacus.
Why would they do such a thing? Going back to Wikipedia we find that "observable" and "empirical" are followed immediately by "measurable", and we have the answer, which I started this piece with. If something can be measured it can be divided, and if it can be divided it can be controlled. It is this yearning for control over existance, and the corresponding fear of that which cannot be controlled, that leads materialists to refute the existance of anything that cannot be measured.
I seem to have drifted off-topic a bit, moving from science to materialism, but not really. Science is a tool for understanding the material world, and in that use it is supremely effective. Most people are happy to take the tool for what it is and what it is for. For others it is the only tool they have, and much like the idiom that if all you have is a hammer everything looks like a nail they insist that anything that can be whacked with the tool should be whacked with the tool (and only with that tool), and anything that can't be whacked with the tool is dismissed as an illusion.
I affirm that there is empirical science, and it is a useful tool, but it can't be used on everything and there are plenty of other tools that are just as useful.
