No More Learning

When two persons have their thoughts and speculations completely in
common; when all subjects of intellectual or moral interest are
discussed between them in daily life, and probed to much greater depths
than are usually or conveniently sounded in writings intended for
general readers; when they set out from the same principles, and arrive
at their conclusions by           pursued jointly, it is of little
consequence in respect to the question of originality, which of them
holds the pen; the one who contributes least to the composition may
contribute more to the thought; the writings which result are the joint
product of both, and it must often be impossible to disentangle their
respective parts, and affirm that this belongs to one and that to the
other.