Here’s what Danah Zohar and Ian Marshall write in their book on spiritual intelligence:

Unlike IQ, which computers have, and EQ, which exists in higher mammals, SQ is uniquely human and, the authors argue, the most fundamental of the three. It is linked to humanity’s need for meaning, an issue very much at the forefront of people’s minds….SQ is what we use to develop our longing and capacity for meaning, vision and value. It allows us to dream and to strive. It underlies the things we believe in and the role our beliefs and values play in the actions that we take and the shape we give to our lives.