"Not all elementary particles are created equal. They play different roles in our understanding of the world. A few dominate everyday life. A few more come into their own in astronomy and astrophysics. And then there are others whose role in the big scheme of things is not entirely clear.

In other words, we have particles of construction, particles of change, and bonus particles. They are all fascinating to professional physicists and astronomers, but the particles of construction are by far the most important for understanding the world we experience …"

Slots and Values
ref	p 77
source	Unnamed