“'Twill not, in this respect, be sufficient for us to use the seeming logic of a famous[46] modern, and say, ‘_We think_; therefore _we are_.’ Which is a notably invented saying, after the model of that like philosophical proposition, that ‘_What is, is_.’ Miraculously argued! If ‘_I am, I am_.’ Nothing more certain! For the _ego_ or I being established in the first part of the proposition, the _ergo_, no doubt, must hold it good in the latter. But the question is, ‘What constitutes the _we_ or _I_?’ And, ‘Whether the I of this instant be the same with that of any instant preceding, or to come.’ For we have nothing but memory to warrant us, and memory may be false. We may believe we have thought and reflected thus or thus; but we may be mistaken. We may be conscious of that, as truth, which perhaps was no more than dream; and we may be conscious of that as a past dream, which perhaps was never before so much as dreamt of. “This is what metaphysicians mean, when they say, ‘That _identity_ can be proved only by _consciousness_; but that consciousness withal may be as well false as real, in respect of what is past.’ So that the same successional _we_ or _I_ must remain still, on this account, undecided. “To the force of this reasoning I confess I must so far submit, as to declare that for my own part, I take my being _upon trust_. Let others philosophize as they are able; I shall admire their strength, when, upon this topic, they have refuted what able metaphysicians object, and Pyrrhonists plead in their own behalf. “Meanwhile, there is no impediment, hinderance, or suspension of action, on account of these wonderfully refined speculations. Argument and debate go on still. Conduct is settled. Rules and measures are given out, and received. Nor do we scruple to act as resolutely upon the mere supposition that _we are_, as if we had effectually proved it a thousand times, to the full satisfaction of our metaphysical or Pyrrhonean antagonist.”[47]