conceptual art

Q1. According to Buchloh, "the traditional criteria of aesthetic judgment - of taste and of connoisseurship - have been programmatically voided" (593). I found this statement interesting because if the aesthetics of a piece are gone, how do you judge the piece of art? He talks about how the aesthetics becomes "on the one hand a matter of linguistic convention" while on the other hand, it functions both as a "legal contract and an institutional discourse" (593). I find this concept hard to grasp. How can the aesthetics of the piece be a "linguistic convention?"

Q2. Buchloh talks about how Conceptual Art "prohibits any and all visuality" from it's artwork (594). He then goes on to discuss the way in which the visual of the "square - would be illegitimate" (596). How - if something is right in front of you and you are looking at it - can the visual of the art be "illegitimate?" Isn't the visual itself what makes it art and why it is so important?