Flourishing, or human flourishing, is the complete goodness of humans in a developmental life-span, that somehow includes positive psychological functioning and positive social functioning, along with other basic goods. The term has gained more usage and interest in recent times, but is rooted in ancient philosophical and theological usages. Aristotle’s term eudaimonia is one source for understanding human flourishing. The Hebrew Scriptures, or the Old Testament, also speak of flourishing, as they compare the just person to a growing tree. Christian Scriptures, or the New Testament, build upon Jewish usage and speak of flourishing as it can exist in heaven. The medieval theologian Thomas Aquinas drew from Aristotle as well as the Bible, and utilized the notion of flourishing in his philosophical theology. More recently, the Positive Psychology of Martin Seligman, Corey Keyes, Barbara Fredrickson, and others, have expanded and developed the notion of human flourishing. Empirical studies, such as those of the Harvard Human Flourishing Program, and practical applications, indicate the importance of the concept and the increasingly widespread use of the term in business, economics, and politics. In positive psychology, flourishing is "when people experience positive emotions, positive psychological functioning and positive social functioning, most of the time," living "within an optimal range of human functioning." It is a descriptor and measure of positive mental health and overall life well-being, and includes multiple components and concepts, such as cultivating strengths, subjective well-being, "goodness, generativity, growth, and resilience." In this view, flourishing is the opposite of both pathology and languishing, which are described as living a life that feels hollow and empty.