But, it may be urged, if a thing happens once, it must happen always; for what is to hinder it? Nay, on the contrary, why, because one particle of matter has a certain property, should all particles have the same? Why, because particles have instanced the property a thousand times, should the thousand and first instance it also? It is _primâ facie_ unaccountable that an accident should happen twice, not to speak of its happening always. If we expect a thing to happen twice, it is because we think it is not an accident, but has a cause. What has brought about a thing once, may bring it about twice. _What_ is to hinder its happening? rather, What is to make it happen? Here we are thrown back from the question of Order to that of Causation. A law is not a cause, but a fact; but when we come to the question of cause, then, as I have said, we have no experience of any cause but Will. If, then, I must answer the question, What is to alter the order of nature? I reply, That which willed it;—That which willed it, can unwill it; and the invariableness of law depends on the unchangeableness of that Will. And here I am led to observe that, as a cause implies a will, so order implies a purpose. Did we see flint celts, in their various receptacles all over Europe, scored always with certain special and characteristic marks, even though those marks had no assignable meaning or final cause whatever, we should take that very repetition, which indeed is the principle of order, to be a proof of intelligence. The agency then which has kept up and keeps up the general laws of nature, energizing at once in Sirius and on the earth, and on the earth in its primary period as well as in the nineteenth century, must be Mind, and nothing else, and Mind at least as wide and as enduring in its living action, as the immeasurable ages and spaces of the universe on which that agency has left its traces. In these remarks I have digressed from my immediate subject, but they have some bearing on points which will subsequently come into discussion. 5. _Speculation._ Speculation is one of those words which, in the vernacular, have so different a sense from what they bear in philosophy. It is commonly taken to mean a conjecture, or a venture on chances; but its proper meaning is mental sight, or the contemplation of mental operations and their results as opposed to experience, experiment, or sense, analogous to its meaning in Shakspeare’s line, “Thou hast no speculation in those eyes.” In this sense I use it here.