When, for example, Christian doctrine has been overlaid from age to age by concretions which had gathered round it, as was the case previously to the Reformation,(1018) it has been free thought which has attacked the system, and, piercing the error, has removed those elements which had been superadded. Or, when the church has attempted to fetter human thought in other departments than its own proper domain of religion, as when the ecclesiastical authorities disgraced themselves by vetoing the discoveries of Galileo,(1019) it has been to free thought that we owe the emancipation of the human mind. Or, when the church linked itself in alliance with a decaying political system, as in the last century in France, it was free thought that recalled to it the lesson to render to Cæsar the things that were Cæsar’s, and to God the things that were God’s. It is instances like these, where free thought has been the means of making undoubted contributions to human improvement, or of asserting toleration, which have led writers to describe it as almost innocuous, and hastily to regard the ratio of the emancipation of the human mind from the teaching of the priesthood to be the sole measure of human improvement. In many instances also, free thought has indirectly contributed to intellectual good, in points where it has ran a greater risk, than in those just cited, of trespassing upon the sacred truths of religion; instances, in fact, where the benefit resulting has been owing to the overruling Providence which brings good out of evil, rather than to any direct intention on the part of those who have exercised it. Examples are to be found in those epochs, when some sudden outburst of knowledge compelled a reconsideration of old truths by the light of new discoveries. The awakening of the mind in the middle age, the Renaissance, the advance of modern science, the birth of literary criticism, are instances of such moments, wherein free inquiry has been a necessity forced on the mind by outward circumstances, not self-prompted. This attitude of inquiry, this exercise of a provisional doubt, was not, like that described, called forth merely by the circumstance that religion had received additions from error, but must have arisen even if the faith once delivered had been preserved uncorrupted. For religion being a fixed truth, while truth in other departments is progressive, it would have been impossible to avoid the necessity of comparison of it with them from time to time, in those spheres where it intersected the field occupied by them.