The advantages arising from a system of copyright are obvious. It is desirable that we should have a supply of good books; we cannot have such a supply unless men of letters are liberally remunerated; and the least objectionable way of remunerating them is by means of copyright. You cannot depend for literary instruction and amusement on the leisure of men occupied in the pursuits of active life. Such men may occasionally produce compositions of great merit. But you must not look to such men for works which require deep meditation and long research. Works of that kind you can expect only from persons who make literature the business of their lives... It is then on men whose profession is literature, and whose private means are not ample, that you must rely for a supply of valuable books. Such men must be remunerated for their literary labour. And there are only two ways in which they can be remunerated. One of those ways is patronage; the other is copyright.
There have been times in which men of letters looked, not to the public, but to the government, or to a few great men, for the reward of their exertions... I can conceive no system more fatal to the integrity and independence of literary men than one under which they should be taught to look for their daily bread to the favour of ministers and nobles. I can conceive no system more certain to turn those minds which are formed by nature to be the blessings and ornaments of our species into public scandals and pests.
We have, then, only one resource left. We must betake ourselves to copyright, be the inconveniences of copyright what they may.
He goes on to oppose, rightly, the extension of copyright many years after the author's demise. But for those who think copyright is "just wrong", that's the straightforward and correct response.