The concept of clear and present danger was once used to defend mandatory vaccination in times of epidemic. And the term conscientious objector, now associated primarily with war, originally referred to people who refused vaccination. Those objectors were not refusing to carry weapons—they were insisting on their right to carry disease. The United Kingdom Vaccination Act of 1853 required the vaccination of all infants and was resisted by many parents. Later legislation allowed for resisters to be repeatedly fined, and those who could not pay had their belongings seized and auctioned, or were imprisoned.
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None of this went over well. In 1898, the English government added a conscience clause to the act, allowing parents to apply for an exemption. This exemption was the precursor to today’s “philosophical” exemptions in the United States, where 15 states allow parents to send unvaccinated children to child care and/or public schools for reasons that are not medical or religious, but philosophical. The conscience clause was vague, requiring only that the objector “satisfy” a magistrate that her objection was a matter of conscience. The new law resulted in thousands of cases of conscientious objection, in some places applying to the majority of all births, as well as a debate about what exactly it meant to possess a conscience.
Before the concept of a conscientious objector was written into law, the term was used by vaccine resisters to distinguish themselves from parents who had simply not bothered to vaccinate their children. The word conscientious was meant to signal that this was an intentional decision made by caring parents. Conscientious objectors argued that a conscience could not and should not be evaluated, and the magistrates themselves were vexed by the problem of whether to demand some sort of evidence to support a claim of conscience. “I don’t understand the act,” one magistrate said in frustration. “I have seen you, and you have told me you have a conscientious objection; I don’t know whether that is enough.” In debating the law, parliamentarians determined that the conscience was very difficult to define.
Today we tend to think of the conscience as an inner voice, or a form of moral intuition. It’s a little cricket whispering in your ear. Your mind talking to itself. The idea that the conscience is an inner source of knowledge has obvious appeal. If your own conscience can tell you what to do in morally significant situations, you don’t need to struggle with others to arrive at justifiable decisions.
Philosophy is not a matter of declaring rigidly held beliefs, but of working out what can be held true in conversation with others. In the Western tradition, going all the way back to Plato, philosophy is based on dialogue. But philosophical exemptions to vaccination laws excuse people from explaining themselves. And the philosophy behind many exemptions remains as remote and ill-defined today as the conscience was in the late 1800s. These exemptions allow parents to offer their fears as justification for not vaccinating their children. The question of whether this is “enough” to justify exposing others to disease is what once frustrated the magistrates charged with judging a claim to conscience. Americans seem to have inherited a folk theory of conscience that confuses firm belief with knowledge. But you can’t know something that isn’t true, though you can certainly believe something that isn’t true. Beyond the confusion of belief with knowledge, our intellectual tradition offers several other theories of conscience. Some explain conscience as a special motivation to avoid wrongdoing or fulfill obligations; others present it as a kind of reflective thinking about the morality of one’s actions.