A great part of these statements would have been acknowledged as true by M. Comte, and belong as much to his theory as to Mr Spencer's. The re-action of all other mental and social elements upon the intellectual not only is fully recognized by him, but his philosophy of history makes great use of it, pointing out that the principal intellectual changes could not have taken place unless changes in other elements of society had preceded; but also showing that these were themselves consequences of prior intellectual changes. It will not be found, on a fair examination of what M. Comte has written, that he has overlooked any of the truth that there is in Mr Spencer's theory. He would not indeed have said (what Mr Spencer apparently wishes us to say) that the effects which can be historically traced, for example to religion, were not produced by the belief in God, but by reverence and fear of him. He would have said that the reverence and fear presuppose the belief: that a God must be believed in before he can be feared or reverenced. The whole influence of the belief in a God upon society and civilization, depends on the powerful human sentiments which are ready to attach themselves to the belief; and yet the sentiments are only a social force at all, through the definite direction given to them by that or some other intellectual conviction; nor did the sentiments spontaneously throw up the belief in a God, since in themselves they were equally capable of gathering round some other object. Though it is true that men's passions and interests often dictate their opinions, or rather decide their choice among the two or three forms of opinion, which the existing condition of human intelligence renders possible, this disturbing cause is confined to morals, politics, and religion; and it is the intellectual movement in other regions than these, which is at the root of all the great changes in human affairs. It was not human emotions and passions which discovered the motion of the earth, or detected the evidence of its antiquity; which exploded Scholasticism, and inaugurated the exploration of nature; which invented printing, paper, and the mariner's compass. Yet the Reformation, the English and French revolutions, and still greater moral and social changes yet to come, are direct consequences of these and similar discoveries. Even alchemy and astrology were not believed because people thirsted for gold and were anxious to pry into the future, for these desires are as strong now as they were then: but because alchemy and astrology were conceptions natural to a particular stage in the growth of human knowledge, and consequently determined during that stage the particular means whereby the passions which always exist, sought their gratification. To say that men's intellectual beliefs do not determine their conduct, is like saying that the ship is moved by the steam and not by the steersman. The steam indeed is the motive power; the