The British philosopher and logician Bertrand Russell asserts, "...provided our use of words is consistent it matters little how we define them." However, L. Susan Stebbing declares, "...but the use of a word already familiar in a certain sense to express a sense different from its original meaning and liable to be confused with it is apt to lead to unfortunate consequences. It is difficult not to slip back to the original meaning, and thus to perplex oneself and others with apparent paradoxes, and even to fall into obvious falsities."