A conceptual paper addresses a question that cannot be answered simply by getting more factual information. A purely conceptual question is one to which factual information is not even relevant.
Purely conceptual question:
What distinguishes species that have moral rights from those that do not have such rights?
Some issues involve both conceptual and factual issues. For example:
Is it morally permissible to kill and eat lobsters?
A conceptual paper may address such an issue, but the central thrust of the paper is not to present dispositive factual information, but instead to present arguments that may either be based upon broadly accepted facts or may proceed from factual assumptions. (If these factual assumptions are later proved false, the arguments in the paper will become irrelevant -- but they have not, strictly speaking, been refuted by the new factual evidence.)
Conceptual question based on factual assumption:
Assuming that lobsters do not experience pain, is it morally permissible to kill and eat them?
Note that the issue might also be addressed from an empirical point of view, based on a conceptual assumption:
Assuming that it is morally permissible to kill and eat animals that do not experience pain, is it permissible to kill and eat lobsters?
The paper would consist of a discussion of whether lobsters experience pain -- a factual question.
Obviously, it would also be possible to address both the factual
and the conceptual issues in the same paper. For this course, however,
I want you to avoid doing that, if for no other reason than that I have
no idea how to evaluate your empirical claims.