Nothing exists except atoms and empty space; everything else is opinion. Democritus, 470 BC-380 BC*. Modern particle physics has broken things down even further and at CERN in Switzerland the Higgs Bosun ("God Particle") at the Large Hadron Collider is believed to have been found.
Down-to-the-nitty-gritty just doesn't work in some cases. It's called reductionism, and in its place we have a relatively recent concept of emergent systems.
Not too long ago with the Human Genome Project, press releases proclaimed that scientists were on the trail of the happiness gene, the depression gene, the agression gene. O Brave New World in which you change a gene and plot a life course. Instead, however, the findings are different. A specific trait arises from the inter-relationship of hundreds of different genes.
As a concept, emergent systems holds the view that human--and societal--behavior cannot be reduced to single characteristics, and thereby change be effected. To use a cliche, the whole is greater than the sum of its parts.
This leads to what Eric Turkheimer, University of Virginia, calls the Gloomy Prospect in terms of hope for some kinds of social reform. His research shows that IQ is harmed by growing up in poverty. How, then, to boost IQ for poor children? That is the Gloomy Prospect. No single element can be changed to elevate scores.
He regards poverty as an emergent system. It does not have a single cause, nor do lower intelligence test scores. As an analogy, you cannot find in an American all the traits of American society, just as you cannot find in a Japanese or Mexican the entire personality of their societies. The societies are part of systems that cannot be broken down into constituent parts and be understood. They must be understood as a whole.
Over the years Turkheimer was able to identify the cumulative effects of poverty but, upon examining likely "culprits" influencing intelligence, he realized that they were emergent, part of a complex system, and changing a few culprits to help IQ was like trying to catch water in a sieve. It couldn't be done. The entire system of poverty as an emergent phenomenon was responsible.
*Another translation in context: By convention sweet is sweet, by convention bitter is bitter, by convention hot is hot, by convention cold is cold, by convention color is color. But in reality there are atoms and the void. That is, the objects of sense are supposed to be real and it is customary to regard them as such, but in truth they are not. Only the atoms and the void are real.