Hume says in the Inquiry On the Human Agreement that ‘ ‘ all the objects of the inquiry human being can of course be divided in two types: relations of ideas and questions in fact ‘ ‘. Followed affirms: ‘ ‘ All the referring reasonings to the questions in fact seem to establish in the relation of cause and efeito’ ‘. Later it continues the inquiry affirming that ‘ ‘ all effect is a different event of its causa’ ‘. From then on, the basic question of the experience enters, that is, that the taken off conclusions of the experience will not be based on the reasoning or another function of the agreement. To explain better as the nature this acts in the explanation of the causalidade is the point – it affirms that this same nature keeps very well moved away from us some of its secrets, granting the right to perceive only one few superficial qualities to us of objects, ‘ ‘ keeping occult them to be able secretos’ ‘. This means that no object discloses for the qualities that appears to the directions, as much the causes had produced that it as the effect that had appeared of it. The vision of these occult natural principles makes in them to assume that whenever to observe similar qualities of an object, the experience goes to wait to find effect similar.

However, Hume then will say that ‘ ‘ one admits unanimously that it does not have connection known between sensible qualities and to be able private, and consequently, that the mind, when arriving at one such conclusion on its constant conjunction and regular’ ‘ , it will not arrive at the result to know on something the nature of these qualities. Then, ahead of this lack of natural explanation, of this ocultamento, it does not have another form to explain these causal inferences not to be for the effect of the habit. The habit supports the inferences. Without the habit the imagination runs untied. ‘ ‘ The habit, through the memory of passed experiences, is the bedding of all the causal inferences, is the only bedding of our belief of that the future will be similar to passado’ ‘.

It is the habit that supports the inferences (in the experience). For Hume, the belief from that similar events come from similar effect only means that ‘ ‘ identical objects had been always placed in identical relations of proximity and sucesso’ ‘ , exactly that such identification is essential for ours ‘ ‘ sobrevivncia’ ‘. Why the alone experience only multiplies objects. It in this manner concludes, then, that ‘ ‘ we never can discover any new idea and we can multiply, but only not increase, the objects of ours esprito’ ‘. The mere product of the imagination is a voluntary act, but the habit is that it modifies and it characterizes the products of the imagination and that determined the way to follow (the habit is determinative).