We can best use Spirit as a synonym of Life, on association with the human qualities of being spirited or enthusiastic, from Greek enthousiazein ‘be possessed or inspired by a god’, which we know today as God.

Etymologically, Spirit derives from a PIE root ‘to breathe’. Anyone who has been close to someone as they die peacefully can see this connection. The breath slowly, slowly disappears as life-giving Spirit drops away.

Many other words have an association with breathing animals, even in esoteric traditions. For instance, Atman, “the real immortal self of human beings, known in the West as the soul”,  derives from Sanskrit ātman ‘breath, spirit; soul, essence, self’. Similarly, in Sanskrit, prāna ‘the cosmic energy that penetrates and maintains the body’, emerging from Ākāsha ‘Æther’, means ‘breath, vital life’, from verbal root prā ‘to fill’, from PIE base *pelə-¹; ‘to fill’. Again, qi (ch’i), a central concept in Taoism and Chinese medicine, denotes “the vital energy, the life force, the cosmic spirit that pervades and enlivens all things”, literally ‘air, breath, gas’.

We see similar relationships between breath, life, soul, and spirit in other languages. For instance, animate derives from the Latin animalis ‘having a soul’, from anima ‘breath, soul’, which, of course, is the root of animal. These words are related to the Swedish anda ‘breath, spirit’ and ande ‘spirit, soul’, cognate with aniti ‘breathe’ in Sanskri, from PIE base *anə- ‘to breathe’.

We can also see these etymological relationships in words in the Bible. For instance, in the Old Testament, the Hebrew words nephesh or nepeš ‘breath; life, life force, soul’ and rûah ‘breath, wind; spirit, mind, heart’ are translated as ‘soul’ and ‘spirit’, respectively. Similarly, in the New Testament, the Greek words psūkhē ‘breath, spirit; life, soul; heart, mind’ and pnuema ‘wind, breath’ are also translated as ‘soul’ and ‘spirit’, respectively. As The Strongest Strong’s Exhaustive Concordance of the Bible tells us, all these words denote ‘the immaterial part of the inner person that can respond to God’.

So the roots of our language clearly indicate that the ancients were well aware of the role that Spirit, arising through the Soul, plays in breathing animals, such as human beings.

As science traditionally excludes Life from consideration, to find Peace by unifying science and spirituality, it is clear that we need to include Spirit in the domain being studied.