Once an opinion is accepted, whatever be the cause of its acceptance, it has a strong tendency to persist. Every time we think along a particular thought-pattern, makes it easier for us to think the same way again. It is quite legitimate to speak of "habits" of thought. The "brain path" becomes so well worn; the pattern of brain-centers becomes so well connected up by continual use, that the nerve current finds a route of practically no resistance, and so it always takes almost exactly the same course.
adj. 确定的,必然的,特定的
pron.