Again, the same duty of reversing our familiar attitude, of inverting our customary proceeding, becomes ours for another reason. The conceptual atomism of common thought leads it to place movement in a lower order than rest, fact in a lower order than becoming. According to common thought, movement is added to the atom, as a supplementary accident to a body previously at rest; and, by becoming, the pre-existent terms are strung together like pearls on a necklace. It delights in rest, and endeavours to bring to rest all that moves. Immobility appears to it to be the base of existence. It decomposes and pulverises every change and every phenomenon, until it finds the invariable element in them. It is immobility which it esteems as primary, fundamental, intelligible of itself; and motion, on the contrary, which it seeks to explain as a function of immobility. And so it tends, out of progresses and transitions, to make things. To see distinctly, it appears to need a dead halt. What indeed are concepts but logical look-out stations along the path of becoming? what are they but motionless external views, taken at intervals, of an uninterrupted stream of movement? Each of them isolates and fixes an aspect, "as the instantaneous lightning flashes on a storm-scene in the darkness." ("Matter and Memory", page 209.) Placed together, they make a net laid in advance, a strong meshwork in which the human intelligence posts itself securely to spy the flux of reality, and seize it as it passes. Such a proceeding is made for the practical world, and is out of place in the speculative. Everywhere we are trying to find constants, identities, non-variants, states; and we imagine ideal science as an open eye which gazes for ever upon objects that do not move. The constant is the concrete support demanded by our action: the matter upon which we operate must not escape our grasp and slip through our hands, if we are to be able to work it. The constant, again, is the element of language, in which the word represents its inert permanence, in which it constitutes the solid fulcrum, the foundation and landmark of dialectic progress, being that which can be discarded by the mind, whose attention is thus free for other tasks. In this respect analysis by concepts is the natural method of common-sense. It consists in asking from time to time what point the object studied has reached, what it has become, in order to see what one could derive from it, or what it is fitting to say of it. But this method has only a practical reach. Reality, which in its essence is becoming, passes through our concepts without ever letting itself be caught, as a moving body passes fixed points. When we filter it, we retain only its deposit, the result of the becoming drifted down to us.