73. Having explained the idea of time, and applied it to the most difficult questions, we may explain this doctrine still farther, by examining what we have already intimated concerning the resemblance between time and space.[29] There is analogy in the difficulties; analogy in the definitions of both ideas; analogy in the illusions which hinder the knowledge of the truth. What we announced before with respect to these two ideas, considering the idea of time as only what it appeared at first sight, we may now assert as the secure result of analytical investigations. I call attention in particular to the following parallel, because it greatly explains the ideas of both. [29] See Ch. III. 74. Space is nothing in itself, distinguished from bodies; it is only the extension of bodies: time is nothing in itself, distinguished from things. It is only the succession of things. 75. The idea of space is the idea of extension in general; the idea of time is the idea of succession in general. 76. Where there are no bodies, there is no space: where there are no things which succeed each other, there is no time. 77. An infinite space, before the existence of bodies, or outside of bodies, is an illusion of the imagination: an infinite time before the existence of things, or outside of them, is also an illusion. 78. Space is continuous: so is time. 79. One part of space excludes all others; one part of time also excludes all others. 80. A pure space, in which bodies are situated, is imaginary: a succession, a time, in which things succeed, is also imaginary. 81. That which is entirely simple has no need of space, and can exist without it: that which is immutable has no need of time, and can exist without it. 82. The simple and infinite is present to all points of space, without losing its infinity: the immutable and infinite is present to all instants of time, without altering its eternity. 83. Two things are distant in space, because there are bodies placed between them; this distance is only the extension of the bodies themselves: two beings are distant in time, because there are other beings placed between them; this distance is the existence of the beings which are placed between. 84. Extension needs no other extension, in which to be placed, otherwise we should have a _processus in infinitum_: the succession of things, for the same reason, needs no other succession in which to succeed. 85. Just as we form the idea of continued succession in space by distinguishing different parts of extension, and perceiving that one excludes the others, so we also form the idea of continued succession of time by distinguishing different facts and perceiving that one excludes the others.