Logic Part 8: Non-Human Logic
It seems highly unlikely that any animal endowed with a very faulty logical processing process would survive for very long or reproduce. Extremely problematic logic, one might imagine, would be highly selected against in evolution and would have been eradicated long before the appearance of humans. In addition, it seems highly unlikely that logic would have sprung into action with the evolution of homo sapiens. Nevertheless, humans seem to possess very complex linguistic communication and tool-making and use not found in other species.
Both of these processes clearly require us to use logical thinking. However, humans are not alone in their ability to use tools. The incredible tool use behaviour of crows shown in 2 videos below supports the idea that non-human species clearly use a kind of procedural logic.
Observation and training of other non-human animals appear to suggest that they engage in causal reasoning and possess procedural logic and memory and “mental templates“.‘Educational’ studies of chimpanzees (particularly an animal named Washoe) can even be seen to teach(!) signing on video.
This suggests that they are capable of engaging in some form of abstract symbolic logic, or at least symbolic communication when interacting with humans or others of the same species. It is thus very tempting to think that animals appear to have behaviours that can be interpreted as being driven by forms of non-human rationality or some representational ability.
It is extremely difficult to imagine how linguistic expression could be formed by animals such as Washoe, a chimpanzee, or Koko the lowland gorilla (who also used American sign language, see video) or in gestures among gorillas when communicating naturally, unless they possess a logic that can handle symbols.
In a very strict logical sense, it could be argued that other animal species possess an innate sense of truth about the way the world is, although perhaps not one that is either epistemic or alethic.
Despite the assertions of some philosophers, we cannot be sure whether or not other animals have thoughts about thoughts due to their subjective nature.