Ideas are not, therefore, a true multiplicity, because they are not things, either material or ideal, and because they do not occupy any space whatsoever. Our imagination may present them to us as so many lights of an ideal sky; but our intelligence warns us that they cannot be separated one from the other and placed side by side. As I have already said: when we think one, we think them all. Or in any event we should, if we had mastered all that there is to be known. So that to our thought ideas appear as constituting one unique whole, a unity, that something which we call science, truth, knowledge. They are not a multitude, for the simple reason that in multiplicity they would be unthinkable. Their connection with and participation in an absolute unity come from the fact that they are the object of thought, and are therefore submitted to its activity, whereby they are ordered, correlated, organised, unified. In order that we may say that one idea contains another, or many others, we must analyse this first idea and define it. This first idea must be distinguished from the others, and they likewise among themselves. It is not therefore sufficient to say that there are these ideas, motionless, inert, lifeless, as they necessarily would be if they existed _per se_, as objects of mere possible contemplation. There must also be some one to analyse them, define them, and distinguish them. It is not enough to have the material of thought, we need thought also to mould and fashion this material, turn it effectively into thought stuff, reduce it to something susceptible of being thought. Ideas as things would in no way be related among themselves. But they do have that relationship which is generated by thought as it thinks them. Thought generates this relationship not as a fixed one, as would be the case if it were inherent in the things themselves; but as a relationship which is being formed by degrees, and which is continuously changing and developing. No ideal, abiding science, existing only as the object of a vague phantasy, can therefore result from this relationship. It constitutes instead a science which is ever re-formed and is never formed; it gives to the ideas an ever renewed aspect: it matures them, elaborates them, perfects them, by concentrating on each one of them the constantly increasing light of the system into which it closely binds them. Ideas, then, as we really think them, are not a minutely fractioned and scattered multiplicity. Nor are they a mass of concurrent elements. They are Thought as it becomes articulate, and gains distinctness by these many Limbs, by these ideas, which exist, all of them, in the process by which they are gradually formed, developed, and complicated, and arrayed in an order which is constantly being renewed and which is never definitely perfected.