Sense of life – the inner perception of the body

In the twelve senses described by Rudolf Steiner, the sense of life is one of the four senses directed at the own body, together with touch, the sense of movement and the sense of balance. It rarely draws attention to itself. That is exactly what makes it interesting to observe.

What the life sense perceives

The sense of life is the internal sense of the organs and the internal life processes. The life sense tells you that you are full, that you have indigestion, or that you have to go to the toilet. You do not sense anything as long as your life processes are all following their normal, harmonious course. The life sense is not registered until one of the life processes is disturbed, or when a person is ill. Other examples of observations made by the life sense are stomach-ache, a congested nose or sinusitis. The organs, and the life sense itself, go unperceived unless something is wrong.

Pain is a serious disturbance which is also perceived with the life sense. The life sense tells you that you have cut your finger, that a muscle hurts or that you bumped your knee on the table-leg.

Generally, the life sense gives information about the physical situation: health, vitality, illness or pain. In this description the life sense uses the vegetative nervous system, which has connections with all the internal organs.

The body as substance

Another type of observation that the life sense can make is the perception of the body as having substance. The life sense makes a person perceive himself or herself as a physical, material body. With only a sense of touch, you would only be able to feel the boundary of your body, so that the body would feel like an empty shell.

This is a subtle distinction, but it can be followed in ordinary experience. Touch tells where the skin meets a chair or a floor. The feeling of heaviness, fullness and inner presence of the body, the sense of being solid and filled, belongs in this approach to the life sense.

Why the life sense stays in the background

Normally speaking, people are not consciously aware of their body or their organs. Attention is not drawn inward, and this makes it possible to focus on the world around. When someone is sick or in considerable pain, he or she is less attentive to the surroundings.

The same holds for the pleasant side of the life sense. A good night's sleep, a meal at the right moment or a walk in fresh air leave behind a general feeling of well-being, of being fresh and awake. Tiredness, thirst and hunger announce themselves in the same diffuse way. None of these feelings has a clear place in the body; they concern the condition of the whole. The tradition therefore describes the life sense as the sense that perceives the harmony or disharmony of the body as a whole, more than any single organ.

Pain as a warning system

The following anecdote illustrates what might happen if the sense of life does not function properly. One afternoon, a couple went to visit friends and left their son at home. When they came home, they could smell scorched flesh and saw their son playing with a candle. He was holding his fingers in the candle's flame and watching them turning black. He did not feel any pain to warn him that what he was doing was dangerous.

This insensitivity is a symptom of leprosy. People with leprosy do not feel pain in the affected parts of the body, so they do not notice when they get cuts or infections, and subsequently do not treat them. The wounds become infected and the infection can penetrate deeply into the body and result in disfigurement.

Pain, and with it the life sense, is a sensory warning system. Without a message that the stomach was full, nobody would know when to stop eating. Nobody would go to the toilet without being able to tell that the bladder was full. Pain protects against further injury. A stab of pain warns you that you are cutting your finger and should stop. If this sense did not function, many safety measures would need to be taken in order to prevent injury and accidents.

Rhythm and the life sense

The life processes are rhythmic. The heart beats, breathing goes in and out, digestion follows the meals, and sleep and waking alternate in a daily cycle. Many of these rhythms go on without being noticed, yet the body keeps track of them: hunger tends to arrive around the usual mealtime, and tiredness around the usual bedtime. When such a rhythm is broken, after a long flight across time zones or a night without sleep, the disturbance is felt as a vague discomfort in the whole body. In the anthroposophical description this, too, is an observation of the life sense. It does not perceive a thing, but a course of events, and it reports mainly when that course departs from its usual pattern.

How physiology describes the same perceptions

Modern physiology uses the word interoception for the perception of the body's internal state. The walls of the stomach, the intestines and the bladder contain stretch receptors that register how full they are. Other receptors respond to chemical changes, for instance in the blood. Sensory nerve fibres from the organs of the chest and abdomen run largely alongside the nerves of the autonomic nervous system; the vagus nerve carries a great deal of this information to the brainstem. In the brain, these signals are processed in several areas, among them the insular cortex.

Pain from the internal organs is often vague and hard to localise. It can even be felt at a different place from its origin, which is known as referred pain: pain from the heart, for example, may be felt in the left arm or the jaw. This fits the observation that the life sense gives an impression of a state, rather than a sharp picture with clear edges like the one sight or touch gives.

Pain from the skin, muscles and joints is different. It is carried by specialised nerve endings, nociceptors, and is usually well localised. A cut finger is felt exactly where it is cut. In the description of the twelve senses both kinds of pain fall under the life sense, because both are disturbances of the body's normal state.

Observing life in others

The life sense is directed at the perception of the own body; with it, the life processes are perceived. But the life sense can also be used to make external observations, by using it in combination with other senses and by empathising.

With practice, the following can be observed:

• health, vitality and illness in other people and organisms.
• pain suffered by another person or animal. You can feel the other's pain when you see something happen, because you have felt that pain before yourself. This pain is felt directly; it does not take much imagination. One must beware, though, of transferring human feelings to plants or animals.
• the space that an object occupies in its surroundings. Is the space it takes up satisfactory, is it filled harmoniously or not?

Vitality in a tree or an animal

The phenomenological approach uses these external observations when looking at plants and animals. A vital tree fills its space with foliage that is full and fresh in colour, its leaves are firm and its shoots grow out evenly. A tree in decline shows thin crowns, dead twigs and leaves that are small or discoloured. The eyes see these details one by one, but the impression of vitality or weakness arises as a whole, and in this approach the life sense has a share in it.

An animal can be looked at in the same way. A healthy cow has a glossy coat, clear eyes and an alert posture; it eats with appetite and lies down to chew the cud. A sick animal stands apart, holds its head low and looks dull. Farmers and vets often see at a glance that something is wrong before they can say what it is. The comparison of the cow with the mouse and the lion on the page Mouse – lion – cow shows how strongly the cow is ruled by its digestive processes, the very processes the life sense perceives.

The question of space belongs here too. Some organisms fill their surroundings in a balanced way, while others seem cramped or scattered. Such observations are not measurements. They are impressions that can be checked by looking again, by comparing with other specimens and by describing precisely what was seen.

The life sense among the twelve senses

In Steiner's scheme, the twelve senses fall into three groups of four. Touch, life, movement and balance are directed at the own body. Smell, taste, sight and warmth connect a person with the surrounding world; the pages on the sense of smell and the sense of temperature describe two of them. Hearing, the sense of word, the sense of thought and the sense of the other person's ego are directed at other human beings.

Within the first group, the life sense takes a middle position. Touch perceives the boundary of the body, and movement and balance perceive what the body does and how it stands in space. The life sense perceives what lies within: the condition of the living body itself.