I am a _Thinking Thing_, that is to say, _doubting_, _affirming_, _denying_, _understanding_ few things, _ignorant_ of many things, _willing_, _nilling_, _imagining_ also, and _sensitive_. For (as before I have noted) though perhaps whatever I _imagine_, or am sensible of, as without me, _Is not_; yet that _manner_ of _thinking_ which I call _sense_ and _imagination_ (as they are only certain _Modes_ of _Thinking_) I am certain are in Me. So that in these few Words I have mention’d whatever I _know_, or at least Whatever as yet I _perceive_ my self to _know_. Now will I look about me more carefully to see Whether there Be not some other Thing in Me, of Which I have not yet taken Notice. I am sure That I am a _Thinking Thing_, and therefore Do not I know what is Required to make _certain_ of any Thing? I Answer, that in this My _first knowledge_ ’tis Nothing but a _clear_, and _distinct perception_ of What I affirm, Which would not be sufficient to make me _certain_ of the _Truth_ of a Thing, if it were _Possible_ that any thing that I so _clearly_ and _distinctly_ Perceive should be _false_. Wherefore I may lay this Down as a _Principle_. _Whatever I Clearly and Distinctly perceive is certainly True._ But I have formerly Admitted of many Things as very _Certain_ and _manifest_, Which I afterwards found to be _doubtful_. Therefore What sort of Things were they? _Viz._ Heaven, Earth, Stars, and all other things which I perceived by my _Senses_. But What did I Perceive of These _Clearly? Viz._ That I had the _Ideas_ or _Thoughts_ of these things in my mind, and at Present I cannot deny that I have these _Ideas_ in Me. But there was some other thing Which I affirm’d, and Which (by Reason of the common Way of Belief) I thought that I _Clearly_ Perceived; Which nevertheless, I did not really Perceive; And that was, that there were Certain Things _Without Me_ from whence these _Ideas Proceeded_, and to which they were exactly like. And this it was, Wherein I was either _Deceived_, or if by Chance I Judged _truly_, yet it Proceeded not from the strength of my _Perception_.