  John Mackie maintained that moral properties, understood broadly along intuitionist lines, are queer because they are inherently motivational, in the sense that when we come to see that some act is good, we are motivated to do it. No other property we know of has such inherent motivational force. If such properties could be understood naturalistically, e.g., as being such as to elicit desire in those who perceive them, then the inherent motivational force of moral properties would not be queer. For if something’s goodness were identical with its being such as to elicit desire when perceived, it would be no surprise that we come to desire it when we perceive it. But intuitionists’ non-naturalism rules out this explanation of the intrinsic ‘to be pursuedness’ of moral properties.