'All judgments' (he says--p. 423), 'except where both the terms are proper names, are really judgments in Comprehension; though it is customary, and the natural tendency of the mind, to express most of them in terms of Extension. In other words, we never really predicate anything but attributes; though, in the usage of language, we commonly predicate them by means of words which are names of concrete objects--because' (p. 426)--'we have no other convenient and compact mode of speaking. Most attributes, and nearly all large bundles of attributes, have no names of their own. We can only name them by a circumlocution. We are accustomed to speak of attributes, not by names given to themselves, but by means of the names which they give to the objects they are attributes of.' 'All our ordinary judgments' (p. 428) 'are in Comprehension only; Extension not being thought of. But we may, if we please, make the Extension of our general terms an express object of thought. When I judge that all oxen ruminate, I have nothing in my thoughts but the attributes and their co-existence. But when by reflection I perceive what the proposition implies, I remark that other things may ruminate besides oxen, and that the unknown multitude of things which ruminate form a mass, with which the unknown multitude of things having the attributes of oxen is either identical or is wholly comprised in it. Which of these two is the truth I may not know, and if I did, took no notice of it when I assented to the proposition, all oxen ruminate; but I perceive, on consideration, that one or other of them must be true. Though I had not this in my mind when I affirmed that all oxen ruminate, I can have it now; I can make the concrete objects denoted by each of the two names an object of thought, as a collective though indefinite aggregate; in other words, I can make the Extension of the names (or notions) an object of direct consciousness. When I do this, I perceive that this operation introduces no new fact, but is only a different mode of contemplating the very fact which I had previously expressed by the words, all oxen ruminate. The fact is the same, but the mode of contemplating it is different. There is thus in all Propositions a judgment concerning attributes (called by Sir W. Hamilton a Judgment in Comprehension) which we make as a matter of course; and a possible judgment in or concerning Extension, which we _may_ make, and which will be true if the former is true.'