One of the more common misunderstandings of the modern age—we might even call it a delusion— is confusing explanation with meaning. Using the scientific method and other empirical techniques, we have been able to explain many of the processes and mechanics of the natural world.
To give explanation, however, is not the same as to ascribe meaning. To answer how things work is not the same as to answer why they do. Showing, for example, the wonderful symbiotic relationships involved in photosynthesis and describing how it works at the molecular level does not explain why there is such a thing as photosynthesis.
To take it further, why do things exist at all? Why is there observable order in the universe rather than chaos? Explanation is not the same as meaning; how is not the same as why.
The Delusion – In modern times, perhaps as a prideful result of being able to explain so much, we often think we have wholly accounted for not just how things work, but whythey do. We have not. Many today like to argue that the material or physical sciences have presented a comprehensive explanation for most things. They have not. By definition, the physical sciences only address physical interrelationships and secondary causes of things.
Put in philosophical terms, the physical sciences deal well with material and efficient causality but are not well equipped or able to answer questions of formal or final causality. Further, the material sciences can address some secondary causality but not primary causality. (Additional information on these topics is available here and here.)
The error of our day, that the physical sciences can provide a comprehensive explanation for nearly everything, is often referred to as scientism. As Bishop Robert Barron and others have rightly pointed out, there is a metaphysical assumption at the basis of all the physical sciences: that reality is intelligible. It is a necessary presumption for the scientific method that things are not mindlessly or haphazardly here.
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