 The argument is elaborated by means of a thought experiment. Suppose you run a hand over a marble statue and over the body of a human being. The hand does nothing but touch and move over the two bodies, but when the animate body is touched, it feels sensations which vary depending on where it is touched; e.g., a tickling sensation occurs when the hand makes contact with the sole of a foot or pit of an arm. The argument continues: “The sensation is entirely ours and not at all in the hand … [I]t would be a great error” to say the hand has a property in addition to motion and touching, namely, “the power to tickle”. Thr arumgent continues: a tickle sensation is entirely within the being who feels it; tickles plainly have no reality unless they are felt; so if the sentient being is removed, the tickle is nothing but an empty name; so it is possible that tastes, etc. “have a similar and no greater reality” (Galileo 1623 [2008: 185–6]).