Bloom's taxonomy was particularly influential in the movement towards specific objectives which began in the 1960s, when verbs like "understand" and "comprehend" were viewed as too vague to be use, and attempts were made to find long lists of actions that would fall under the rubric. Detailing seems quite reasonable, but it had led almost always to long lists to low-level objectives. So the recent trend is to return to the imprecise view of understanding, as witnessed by the new popularity of the old proverb, " I hear,and I forget. I see, and I remember. I do, and I understand" mentioned in the NCTM Professional Teaching Standards. This adage contrasts with a statement that many teachers make, "My students can do it, but they don't understand what they are doing.