Consider sharp things: a razor’s edge, a malevolent tongue, a sharp musical note, an acute angle.
Consider soft things: the stuff inside an egg, a flower petal, a soothing voice, a baby’s skin.
Anyone could add more examples to these lists but, interestingly, people anywhere would agree that the designation “sharp” or “soft” applies to the things listed. A range of senses is used in determining the quality of sharp: the sharp edge of a blade, sword, or piece of paper (ouch, paper cut!); a precipice (the eyes see the sharp drop); angles can be sharp. Then there is the quality of quick sharp mind. A sharp note requires the ear. A sharp tongue is felt through the emotions, as well as heard in the tone of voice and probably seen in body language.
From an esoteric or causative perspective, it is quality and energy that determines the shape, texture, and nature of something. The Science of the Seven Rays is one study of that causative perspective. Your qualities of mind, interests, fears and frustrations, emotional tendencies, and personality traits are demonstrations of your Rays. So is your life purpose and that which brings you deep fulfillment.
Graphic: Happiness on DeviantART