Suppose lightning strikes a dead tree in a swamp; I am standing nearby. My body is reduced to its elements, while entirely by coincidence (and out of different molecules) the tree is turned into my physical replica. My replica, The Swampman, moves exactly as I did. But there is a difference. My replica can’t recognize my friends; it can’t recognize anything, since it never cognized anything in the first place
These bizarre examples attempt to prove one conceptual point or another by deliberately reducing all but one underappreciated feature of some phenomenon to zero, so that what really counts can shine through. The Twin Earth example sets internal similarity to a maximum (you are whisked off to Twin Earth without being given a chance to register this huge shift) so that external context can be demonstrated to be responsible for whatever our intuitions tell us. The Swampman intuition pump keeps both future dispositions and internal states constant and reduces “history” to zero. Thus these thought experiments mimic scientific experiments in their design, attempting to isolate a crucial interaction between variables by holding other variables constant. A problem with such experiments is that the dependent variable is intuition—they are intuition pumps—and the contribution of imagination in the generation of intuitions is harder to control than philosophers have acknowledged.
Source:
Philosopher Daniel Dennett’s Book Intuition Pumps
