Science is about explaining the world rationally (ie, without Gods), because with Gods such explanations are many (per definition), all of which are contradictory by being endless regressions (ie, if God created and rules the world, who, then, created and rules God?). With Gods every such explanation is thus irrational.
A fundamental question for the rational approach is the difference between true and false. How can we “prove” that something is true or false? Considering this question, we can understand that proving that something is true is impossible, since it requires pre-knowledge of what is true, ie, we can’t prove that something is true without knowledge of what is true. This attempt is thus in practice an endless regression. Instead, we can only prove that something is false by empirical (ie, practical) tests. It means that we have to search truths by peeling off falsehoods like how we can peel onions, hoping to be left with the truths in the end (ie, in the middle of the onions).
Science is thus not just a matter of measuring the world, but rather a kind of reasoning. It fundamentally searches truths by empirically dismissing falsehoods. A fundamental question concerning this approach is, however, if there is something (to be found) in the middle of onions. If there isn’t, then science is an endless endeavor. The answer to this question was given when Bertrand Russell formulated his paradox (the so-called “Russell’s paradox”), and it was that there isn’t. Russell’s paradox thus revealed that neither science can find truths.
So, here we are – having concluded that we can’t reach truths at all. The world being just as delusive as it always have been. In this context, we can thus just decide which approach we prefer. The question is thus no longer what the truth is, but which future we prefer, and thus which approach we have have to adopt to promote this future. The question is no longer about ideologies, but about the practical reality.