The colourful name that keynes provided to a single regarding the crucial ingredients of financial success: confidence. Based on Keynes, animal spirits are a certain sort of confidence, "naive optimism". He suggested this in the feeling that, for entrepreneurs specifically, "the very thought of ultimate loss which often overtakes pioneers, as experience certainly informs us and them, is reserve as a healthy man sets aside the hope of death". Where these animal spirits originate from is something of a mystery. Definitely, efforts by politicians yet others to talk up self-confidence through positive noises about financial prospects have seldom done much effective.
The nerves conduct the animal spirits to act upon the muscles, and in their turn convey the impressions of the organs to the brain.