88. Two words of similar outline, ordinarily and necessarily distinguished by position, may be distinguished for phrasing purposes by adopting it as an invariable rule that one of the words shall never be admitted into any phrase (except of course when it begins a phrase), while the other word may be freely joined. This is called distinction by Exclusion. For instance, indeed and no doubt, perfectly distinguished by difference of position when unconnected with other words, are liable to conflict when phrased, except at the beginning of phrases. To obviate this difficulty, it is generally adopted as a rule that indeed must not be admitted into any phrase except at the beginning, while no doubt may be phrased freely. It is obvious that, if one of the words or expressions be always written separately and in position, the other, though freely phrased without regard to position, cannot be mistaken.