We tend to assume that science is different to ideology, that it is more real or valid, because it deals in physical evidence. However, when we look at the history of philosophy we soon see that science is itself an ideology, albeit a particularly fruitful one. At the very least, science is informed and contained within ideologies and therefore inseparable from them. It is important to understand this, not in order to cast doubt on science as such, but in order to acknowledge that it might not be able to teach us everything.
Ideologies are explanations of, or ways of understanding the world. They are self-contained systems of belief which stand alone from each other. Adherents of an ideology believe that they know the truth, the whole truth, the only possible truth. Religions are ideologies and so are many political and philosophical standpoints. Science is an ideology based on a rationalist, mechanistic wordview, characterised by empiricism, the belief that we can learn everything there is to learn by physical means. Galileo, in the 17th century, was amongst the earliest and most notable adherents to this philosophical standpoint. 'Measure what can be measured and make measurable what cannot be measured' he said. Other ideologies rely on less concrete justifications like faith and spirituality.
There was a time before science. In Aristotle's time, philosophers were still arguing about whether human reason was a reliable basis for knowledge. He and Plato were also discussing what came first, the idea of an object or the object itself. Plato thought that there was an objective world of ideas, where the ideal forms came from. There was some kind of mind of God that we had access to and from which came all of our ideas. Aristotle believed the opposite, that we do not form ideas, notions of things, until we have taken them in through our senses. 'Nothing exists in consciousness that has not been first experienced by the senses.' This is a forerunner of our rational, empirical science, and it clearly had an philosophical/ideological basis. Aristotle also believed that there was causality in everything, that animals lived so that humans could eat them, or that it rained because the plants need water.
Galloping forward through history to the Middle Ages, a completely different ideology held sway. During this period science, or even the aspiration to learn about nature, was blasphemy. It was not for mere humans to look into the intricate workings of God. It took someone of the intellectual calibre of Thomas Aquinas to come up with a synthesis between rational enquiry and the received religion. He came up with formal arguments that supported the religious viewpoint. He declared that not only faith, but also rational thought and observation of 'natural laws' can bring us to a closer understanding of God. He began to use techniques of observation and record keeping in order to prove that the Bible was right. He also accepted that some aspects of the Bible could not be explained empirically, that there was room for experiencing God's mysteries. Aquinas's science was rooted in, and inseperable from, his ideology.
Scientific method was born out of the Renaissance which itself was a reaction against the heavy loads that religion had placed upon people over the previous few hundred years. There was an upsurge in individualism, humanism and the powers of the human intellect. While it cannot be denied that scientific method has been, and continues to be, very useful to us, it is clear that it had an ideological, rather than objective, basis.
Scepticism is as old as Aristotle, older even. The original sceptic believed that we couldn't actually know anything for sure, that we can't even trust our own physical senses. Nowadays a sceptic believes that we can only know what can be weighed, measured, tested with our physical senses.
These are both philosophical standpoints. Neither constitutes objective reality.
History aside, we are living in a world awash with differing ideologies about the nature of existence and our place in the cosmos. When we understand that science is itself an ideology, it opens up other avenues of exploration which cannot be examined by empirical methods.