consent

"What is CONSENT?

A concurrence of wills. Express consent is that directly given, either lira voce or in writing. Implied consent is that manifested by signs, actions, or facts, or by inaction or silence, which raise a presumption that the consent has been given. Cowen v. Paddock, 62 Hun, 022, 17 N. Y. Supp. 3SS. Consent in an act of reason, accompanied with deliberation, the mind weighing as in a balance the good or evil on each side. 1 Story, Eq. Jur. "

http://thelawdictionary.org/consent/

Karl seems to be arguing "implied consent" here... the problem of course is his assumption that the consenting parties (us), have been in full control of their faculties and fully exercising free will at all times... imho, that is far from the case.