Godfrey-Smith, Peter. _Other Minds: The Octopus, the Sea, and the Deep Origins of Consciousness_. First edition. New York: Farrar, Straus and Giroux, 2016. # Progressive Summary This is a philosophy book that explores consciousness through investigating the minds of cephalopods. Cephalopods include octopus, squid, and cuttlefish. # Quotes > Cephalopods are an island of mental complexity in the sea of invertebrate animals. Because our most recent common ancestor was so simple and lies so far back, cephalopods are an independent experiment in the evolution of large brains and complex behavior. If we can make contact with cephalopods as sentient beings, it is not because of a shared history, not be- cause of kinship, but because evolution built minds twice over. This is probably the closest we will come to meeting an intel- ligent alien. > ... the sea is the original home of the mind, or at least of its first faint forms. > Doing philosophy is largely a matter of trying to put things together, trying to get the pieces of very large puzzles to make some sense. Good philosophy is opportunistic; it uses whatever information and whatever tools look useful. --- > The receptors on the surfaces of bacterial cells are sensitive to many things, and these include chemicals that bacteria themselves tend to excrete for various reasons—sometimes just as overflow of metabolic processes. This may not sound like much, but it opens an important door. Once the same chemicals are being sensed and produced, there is the possibility of coordination between cells. We have reached the birth of social behavior. > The chemistry of life is an aquatic chemistry. We can get by on land only by carrying a huge amount of salt water around with us. And many of the evolutionary moves made at these early stages—those giving birth to sensing, behavior, and coordination—would have depended on the sea’s free movement of chemicals. > Sensing and signaling between organisms gives rise to sensing and signaling within an organism. A cell’s means for sensing the external environment become a means to sense what other cells within the same organism are up to, and what they might be saying.