Introduction

Even if B's consent is given completely willingly and even if there is no deception, B's token of consent is morally transformative only if she is suitably competent, that is, only if she has the requisite emotional and cognitive capacities. As with other issues that have been discussed, we can understand the need for these requirements in terms of both autonomy and utility. An agent's act is autonomous or self-directing when she is motivated by her appreciation of the reasons provided by her situation. One who lacks certain cognitive or emotional capacities is not capable of making decisions consistent with those reasons. She may not understand her long-term interests or have the emotional capacity to delay gratification. And she may be unable to make choices that are consistent with her deepest values or preferences because those have not been formed (in the case of children) or perhaps cannot ever be formed (in the case of the severely retarded) or because those values are distorted (false consciousness).

From a utilitarian or “mutual benefit” account of consensual transactions, we cannot assume that B's impaired consent is likely to be of benefit to B. People frequently make competent decisions that are not to their advantage ex post, but we can ordinarily assume that they are to their benefit ex ante, unless they choose to interact altruistically with others to their own detriment.