The Living Force
Reading Damasio's book in light of the Work is certainly beneficial, as it makes the case for why we should aim at maintaining a state of self-observation in regard to various feelings that we experience; they arise from the way the "machine" operates.
The circumstances, actual or recalled from memory, that can cause feelings are infinite. By contrast, the list of elementary contents of feelings is restricted, confined to only one class of object: the living organism of their owner, by which I mean components of the body itself and their current state. But let us dig deeper in this idea, and note that the reference to the organism is dominated by one sector of the body: the old interior world of the viscera that are located in the abdomen, thorax, and thick of the skin, along with the attendant chemical processes. The contents of feelings that dominate our conscious mind correspond largely to the ongoing actions of viscera, for example, the degree of contraction or relaxation of the smooth muscles that form the walls of tubular organs such as the trachea, bronchi, and gut, as well as countless blood vessels in the skin and visceral cavities. Equally prominent among the contents is the state of the mucosae — think of your throat, dry, moist, or just plain sore, or of your esophagus or stomach when you eat too much or are famished. The typical content of our feelings is governed by the degree to which the operations of the viscera listed above are smooth and uncomplicated or else labored and erratic. To make matters more complex, all of these varied organ states are the result of the action of chemical molecules — circulating in the blood or arising in nerve terminals distributed throughout the viscera — for example, cortisol, serotonin, dopamine, endogenous opioids, oxytocin. Some of these potions and elixirs are so powerful that their results are instantaneous. Last, the degree of tension or relaxation of the voluntary muscles (which… are part of the newer interior world of the body frame) also contributes to the content of feelings. Examples include the patterns of muscular activation of the face. They are so closely associated with certain emotional states that their deployment in our faces can rapidly conjure up feelings such as joy and surprise. We do not need to look in the mirror to know that we are experiencing such states.
In sum, feelings are experiences of certain aspects of the state of life within an organism. Those experiences are not mere decoration. They accomplish something extraordinary: a moment-to-moment report on the state of life in the interior of an organism.