In this article, we will consider how far we might be said to be active in forming our beliefs; in particular, we will ask to what extent we can be said to be free in believing what we want to believe. It is clear that we ought to believe only what is really so, at least in so far as it lies in our power to determine this, but reflection shows that, regrettably, we do not confine our beliefs to what we have evidence for, nor do we always believe in accordance with the evidence we do have. So it is natural to conclude that non-intellectual factors may be at work here; such, at least, was the view of Descartes, who attributed error to the influence of our will in leading us to assent to judgments which go beyond the evidence presented by our infallible intellect. This view has some initial plausibility when we think of cases in which emotional considerations lead people to take up and genuinely believe things they have no evidence for, but it is not a view which has received much support from modern philosophers. So, in Part 1 we will look at criticisms levelled against Descartes' view by J. L. Evans, and in Part 2 we will see how far Descartes can be defended. Our conclusions here will lead us to give in Part 3 a general account of the influence of the will in beliefs. We will suggest that we are always responsible for our explicit beliefs, even though it is not true that we can simply believe what we like. Thus we will reject the idea that a man can consciously know something, and at the same time, by will power, believe the opposite. Belief is not then totally free, but we will argue that people do sometimes form beliefs which go against what they should and could believe, and that this can in a way be put down to the influence of the will. Finally we will consider some of the ways in which it is possible to influence our beliefs by willed acts over a long period of time, though this is not the way that we clami that the will might be said to play a part in every judgment that we make.