Nephrite Greek "λίθος νεφριτικός"; "νεφρός λίθος", which means 'kidney stone' and is the Latin and Greek version of the Spanish "piedra de ijada" (the origin of "jade" and "jadeite"). Accordingly, nephrite jade was once believed to be a cure for kidney stones. Besides the terms already mentioned, nephrite has the following synonyms and varieties: "aotea", "axe-stone", "B.C. jade", "beilstein", "kidney stone", "lapis nephriticus", "nephrit", "nephrita", pounamu, "New Zealand greenstone", "New Zealand jade", "spinach jade" (dark grayish green), and "talcum nephriticus". "Tomb jade" or "grave jade" are names given to ancient burial nephrite pieces that have a brown or chalky white texture
Theory of forms experience because the forms are not in the physical world. Therefore, our real knowledge of the forms must be the memory of our initial acquaintance with the forms in heaven. Therefore, what we seem to learn is in fact just remembering. No one has ever seen a perfect circle, nor a perfectly straight line, yet everyone knows what a circle and a straight line are. Plato utilizes the tool-maker's blueprint as evidence that Forms are real:... when a man has discovered the instrument which is naturally adapted to each work, he must express this natural form, and not others which