Ancient Greek members of the Skeptical School taught methods or habits that helped people to live better. One method involved pondering how different the world might seem to different animals, considering that other species have diverse types of eyes, ears, and tongues; preferences and aversions; and perhaps whole senses unknown to us.
Skeptics said that we are animals and not fundamentally different from the “so-called irrational animals.” Meditating on examples of animal psychology would prevent people from believing that their own experience was true or that the pursuit of truth was possible. In turn, suspending judgment was a path to inner peace and good treatment of others.
In this spirit, consider the octopus, as described in detail by the philosopher Peter Godfrey-Smith. People who study this animal almost universally conclude that it is curious, intelligent, and interactive and that each octopus has a personality that persists over time. Yet the species is so remote from us on the evolutionary tree that it is like an alien visitor to our planet. Or we could be the aliens on theirs.
For one thing, an octopus has quite different senses from ours, such as suckers that each have 10,000 sensors and eyes of a fundamentally different design. Since an octopus lives underwater and has a soft and flexible body, its whole relationship with its environment must be profoundly different from ours.
I gradually became who I am over many years–the first period now barely a memory for me–and I was deeply connected to other people from the start. I have persisted for almost six decades, building up (and losing) memories. An octopus emerges from an egg and for lives for two years, if it’s lucky, before it dies of old age. Its combination of substantial intelligence and a brief lifespan is unusual on earth and would presumably give it a different sense of time from mine.
An octopus doesn’t have a brain, because its complex nervous system is distributed through its body, and its arms have considerable autonomy. “Octopuses [may] not even track where their own arms might be” (p. 67). Nevertheless, each octopus functions as a coherent organism with an individual personality.
I think of myself as one thing, my body parts as something a bit different (because I control them imperfectly), and the external world as something distinct from both my self and my body. This experience deeply influences my assumptions about fundamentals like self and other, thought and matter, cause-and-effect, intention, and the objective world. It is hard to believe that an octopus feels the same way, yet my experience is no more valid or true.
If you doubt that an octopus has enough mental capacity to have a model of its own world, fine—just imagine an extraterrestrial creature with a similar design as an octopus and 10 times as many neurons. It doesn’t matter whether an alien like that exists on other planets, only that it is plausible. The thought-experiment is enough to tell us that we experience just one of many possible worlds.
Sources: Sextus, Outlines of Pyrhhonism (see 1.13:61 on humans as animals); Peter Godfrey-Smith, Other Minds: The Octopus, the Sea, and the Deep Origins of Consciousness (Farrar, Straus and Giroux, 2017). See also: thinking both sides of the limits of human cognition; ‘every thing that lives is holy’: Blake’s radical relativism;
