 A different argument by Churchland (1985, 44–45) asks what the constructive empiricist would say about beings who are like us except that they are born with electron microscopes permanently attached to their left eyes. Churchland says that the electron-microscope-eye humanoids would count viruses as part of their ontology, and yet by the constructive empiricist’s lights we can’t, even though we are functionally the same as the humanoids when we put our left eye against the viewfinder of an electron microscope.