This will require some seeds, perhaps navy beans or black beans. Choose a seed that will contrast nicely with your carpet and large enough to easily clean up.
"So," as you check a patient's leg length or palpate their spine, "Tell me, what causes disease--like a cold or the flu? What causes that?"
"Well, germs of course," the patient likely responds.
"Really?" That's all it takes is germs? So the germs on that headrest paper are likely to cause a disease?" you query.
To remain congruent with such a core belief, most patients will answer in the affirmative. By now the patient is upright and can see your outstretched hand.
"Germs are like these seeds (beans). They only cause disease when the circumstances are just right," you say, tossing the beans on your carpet. "Are these seeds likely to germ-inate? Of course not. It takes more than just germs."