How does Faith explain the tree's connection to people?

In Chapter 35, after arriving in the cave, Faith sees that Agatha and the Mendacity Tree seem to have an instant connection, and is surprised that she feels jealous. Crock flinches each time a tendril from the tree touches him. Faith taunts him, asking if he is afraid. She then claims she can explain the tree, that it does form a bond with a person but “the rest is just a matter of currents in the magnetic field” (362). Agatha dismisses the theory of animal magnetism.