or Existence. By Means of it alone we attain any Assurance concerning Objects, that are remov'd from the present Testimony of our Memory and Senses. The only immediate Utility of all Science is to teach us, how to controul and regulate future Events by their Causes. Our Thoughts and Enquiries are, therefore, every Moment employ'd concerning this Relation. And yet so imperfect are the Ideas we form concerning it, that 'tis impossible to give any just Definition of Cause, except what is drawn from something extraneous and foreign to it. Similar Objects are always conjoin'd with similar. Of this we have Experience. Suitable to this Experience, therefore, we may define a Cause to be an Object, follow'd by another, and where all the Objects, similar to the first, are follow'd by Objects, similar to the second. The Appearance of a Cause does always convey the Mind, by a customary Transition, to the Idea of the Effect. Of this also we have Experience. We may, therefore, suitable to this Experience, form another Definition of Cause, and call it, an Object, follow'd by another, and whose Appearance always conveys the Thought to that other. But tho' both these Definitions be drawn from Circumstances, foreign to the Cause, we cannot remedy this Inconvenience, or attain any more perfect Definition, which may point out that Circumstance in the Cause, which gives it a Connexion with its Effect.We
