The positive system could only work practically were human nature to suffer a complete change--a change which it has no spontaneous tendency to make, which no known power could ever tend to force on it, and which, in short, there is no ground of any kind for expecting.
There are two characteristics in men, for instance, which, though they undoubtedly do exist, the positive system requires to be indefinitely magnified--the imagination, and unselfishness.

The work of the imagination is to present to the individual consciousness the remote ends to which all progress is to be directed; and the desire to work for these is, on the positive supposition, to conquer all mere personal impulses.

Now men have already had an end set before them, in the shape of the joys of heaven, which was far brighter and far more real to them than these others can ever be; and yet the imagination has so failed to keep this before them, that its small effect upon their lives is a commonplace with the positivists themselves.

How then can these latter hope that their own pale and distant ideal will have a more vivid effect on the world than that near and glowing one, in whose place they put it?
Will it incite men to virtues to which heaven could not incite them?
or lure them away from vices from which hell-fire would not scare them?
Before it can do so, it is plain that human nature must have completely changed, and its elements have been re-mixed, in completely new proportions.

In a state of things where such a result was possible, a man would do a better day's work for a penny to be given to his unborn grandson, than he would now do for a pound to be paid to himself at sunset.
For argument's sake, however, let us suppose such a change possible.