blunder is not economic, but logical. The question is--what is the measure of value? I say then that the phrase--'measure of value' is an equivocal phrase; and, in Mr. Malthus's use of it, means indifferently that which determines value, in relation to the _principium essendi_, and that which determines value, in relation to the _principium cognoscendi_. Here, perhaps, the reader will exclaim--'Avoid, Satanas!' to me, falsely supposing that I have some design upon his eyes, and wish to blind them with learned dust. But, if he thinks _that_, he is in the wrong box: I must and will express scholastic phrases; but, having once done this, I am then ready to descend into the arena with no other weapons than plain English can furnish. Let us therefore translate '_measure of value_' into '_that which determines value_:' and, in this shape, we shall detect the ambiguity of which I complain. For I say, that the word _determines_ may be taken subjectively for what determines X in relation to our knowledge, or objectively for what determines X in relation to itself. Thus, if I were to ask--'What determined the length of the racecourse?' and the answer were--'The convenience of the spectators who could not have seen the horses at a greater distance,' or 'The choice of the subscribers,' then it is plain that by the word 'determined,' I was understood to mean 'determined objectively,' _i. e._ in relation to the existence of the object; in other words, what _caused_ the racecourse to be this length rather than another length: but, if the answer were--'An actual admeasurement,' it would then be plain that by the word 'determined,' I had been understood to mean 'determined subjectively,' _i. e._ in relation to our knowledge;--what ascertained it?--Now, in the objective sense of the phrase, 'determiner of value,' the measure of value will mean _the ground of value_: in the subjective sense, it will mean _the criterion of value_. Mr. Malthus will allege that he is at liberty to use it in which sense he pleases. Grant that he is, but not therefore in both. Has he then used it in both? He will, perhaps, deny that he has, and will contend that he has used it in the latter sense as equivalent to the _ascertainer_ or _criterion of value_. I answer--No: for, omitting a more particular examination of his use in this place, I say that his use of any word is peremptorily and in defiance of his private explanation to be extorted from the use of the corresponding term in him whom he is opposing. Now he is opposing Mr. Ricardo: his _labour which X commands_--is opposed to Mr. Ricardo's _quantity of labour which will produce X_. Call the first A, the last B. Now, in making B the determiner of value, Mr. Ricardo means that B is the ground of value: _i. e._ that B is the answer to the question--what makes this hat of more value than this pair of shoes? But, if Mr. Malthus means by A the same thing, when by his own confession he has used the term _measure