Man, The Measure Of All Things

The dwarf Motsognir tells Skafloc Elven-Fosterling:

"'Let me tell you, boy, that you humans, weak and short-lived and unwitting, are nonetheless more strong than elves and trolls, aye, than giants and gods. And that you can touch cold iron is only one reason. Ho!'" (Hrolf Kraki's Saga, p. 33)

How are we weak yet stronger? I think that the real reason is that it is we who imagine all the others. Later, Imric, earl of Britain's elves, tells his lord, the Erlking:

"'I need not remind you that humans can do much which is barred to elf, troll, goblin or the like. They may use every metal, they may touch holy water and walk on holy ground and speak the name of the new god - aye, the old gods themselves must flee some things which humans have the freedom of.'" (pp. 34-35)

In the fictional universe shared by Neil Gaiman's The Sandman and Mike Carey's Lucifer, it is changes in human beliefs that have made the new god increasingly stronger than the old gods. In The Broken Sword, Odin, devious devil that he is, shape-shifts to resemble Satan in order to mislead a witch. He tells her that the White Christ is more powerful than gods, demons or magic and adds:

"'Nor can you hope to understand how [Fate/Destiny/Wyrd etc] exists together with the freedom wherof I spoke, any more than you can understand how there are both old gods and new." (p. 38)

Freedom can coexist with determinism because it is merely absence of constraint, not a sort of conscious quantum event. Odin raises the question of old and new gods but does not answer it.

Human beings, much bigger than subatomic particles but much smaller than the cosmos, are uniquely, in our experience, self-conscious and able to gain some measure of knowledge and understanding of both microcosm and macrocosm. In some sense and with all due humility, we are the measure of all things. See here.