Satisfactory Quotes - page 2
I rise, Mr. President, for the purpose of announcing to the Senate that I have satisfactory evidence that the State of Mississippi, by a solemn ordinance of her people in convention assembled, has declared her separation from the United States. Under these circumstances, of course, my functions are terminated here. It has seemed to me proper, however, that I should appear in the Senate to announce that fact to my associates, and I will say but very little more. The occasion does not invite me to go into argument, and my physical condition would not permit me to do so if it were otherwise; and yet it seems to become me to say something on the part of the state I here represent, on an occasion so solemn as this.
Jefferson Davis
First of all I want to remind you of the essential features of models. In my opinion they are: (i) drawing up a list of the variables to be considered; (ii) drawing up a list of the equations or relations the variables have to obey and (iii) testing the validity of the equations, which implies the estimation of their coefficients, if any. As a consequence of especially (iii) we may have to revise (i) and (ii) so as to arrive at a satisfactory degree of realism of the theory embodied in the model. Then, the model may be used for various purposes, that is, for the solution of various problems. The advantages of models are, on one hand, that they force us to present a "complete" theory by which I mean a theory taking into account all relevant phenomena and relations and, on the other hand, the confrontation with observation, that is, reality. Of course these remarks are far from new.
Jan Tinbergen