Deceiving versus manipulating: An evidence-based definition of deception

What distinguishes deception from manipulation? Cohen (Australasian Journal of Philosophy, 96, 483 and 2018) proposes a new answer and explores its ethical implications. Appealing to new cases of “non-deceptive manipulation” that involve intentionally causing a false belief, he offers a new definition of deception in terms of communication that rules out these counterexamples to the traditional definition. And, he leverages this definition in support of the claim that deception “carries heavier moral weight” than manipulation. In this paper, I argue that these cases of “non-deceptive manipulation” are even more prevalent than Cohen suggests—especially in the digital world. Thus, if his moral claim were correct, a lot of what is happening on the internet these days would constitute moral improvement over old-fashioned deception. Fortunately, we are not forced to accept this counterintuitive conclusion. Cohen's definition must be rejected because it incorrectly rules out clear instances of deception. In this paper, I defend a definition of deception in terms of evidence that does correctly distinguish between deception and non-deceptive manipulation. Moreover, it does not support Cohen's claim that deception is morally worse than other forms of manipulation.