This is not a course in philosophical speculation, nor is it concerned with precise terminology. It is concerned only with Atonement, or the correction of perception. The means of the Atonement is forgiveness. The structure of "individual consciousness" is essentially irrelevant because it is a concept representing the "original error" or the "original sin." To study the error itself does not lead to correction, if you are indeed to succeed in overlooking the error. And it is just this process of overlooking at which the course aims.
All terms are potentially controversial, and those who seek controversy will find it. Yet those who seek clarification will find it as well. They must, however, be willing to overlook controversy, recognizing that it is a defense against truth in the form of a delaying maneuver. Theological considerations as such are necessarily controversial, since they depend on belief and can therefore be accepted or rejected. A universal theology is impossible, but a universal experience is not only possible but necessary. It is this experience toward which the course is directed. Here alone consistency becomes possible because here alone uncertainty ends.
This course remains within the ego framework, where it is needed. It is not concerned with what is beyond all error because it is planned only to set the direction towards it. Therefore it uses words, which are symbolic, and cannot express what lies beyond symbols. It is merely the ego that questions because it is only the ego that doubts. The course merely gives another answer, once a question has been raised. However, this answer does not attempt to resort to inventiveness or ingenuity. These are attributes of the ego. The course is simple. It has one function and one goal. Only in that does it remain wholly consistent because only that can be consistent.
The ego will demand many answers that this course does not give. It does not recognize as questions the mere form of a question to which an answer is impossible. The ego may ask, "How did the impossible occur?", "To what did the impossible happen?", and may ask this in many forms. Yet there is no answer; only an experience. Seek only this, and do not let theology delay you.
You will notice that the emphasis on structural issues in the course is brief and early. Afterwards and soon, it drops away to make way for the central teaching. Since you have asked for clarification, however, these are some of the terms that are used.