What is "perquisite of tenure "? Is it special right of possessing something or building in this context?
ex)Though I am more sympathetic to the argument that important ideas be aired than to the argument that they should sometimes be suppressed, I think it is a debate we need to have. Tragically, however, there are few signs that the debates will happen in the place where we might most expect it; academia. Though academics owe the extraordinary perquisite of tenure to the ideal of encouraging free inquiry and the evaluation of unpopular ideas, all too often academics are the first to try to suppress them.
In this sentence, I think it would mean:
Though academics owe the extraordinary (perks or privilege of tenure) to the ideal of encouraging free inquiry and the evaluation of unpopular ideas, all too often academics are the first to try to suppress them.
Tenure, in this usage, is a system whereby teachers cannot be fired after they have been with the university a certain number of years.
The basic idea of tenure is to allow researchers freedom to pursue research without pressure from the university. The researcher doesn't have to fear for his job if he wants to look into something the administration might not favor.
It generally works out pretty well, though of course some might use tenure as a free ride to coast on through to retirement. No worse than any other civil servant...