 Another rationale surrounds self-ownership: we are presumed to hold proprietary rights over ourselves and our bodies, perhaps in line with John Locke’s idea that “every Man has a  Property  in his own Person” (Locke 1988, V. 27, 305). Naturally, once an owner’s consent is given, the alleged proprietary prohibition on access and on direct impact is removed. This rationale may better explain why we must normally grant our permission, even for medical intervention that is safe, low-impact, and clearly beneficial, and requires no agency on our part. Trespass into a private sphere can be forbidden even when it involves mere touching, and the owner is foolish or selfish to reject it (Archard 2008, 27f; Thomson 1990, ch. 8; Nozick 1986).