Res Cogitans

How can I be sure about the world my eyes are seeing?
 Is this all the truth or just some kind of coherent dream?
 What if there's a deceiver god who's playing with my head?
 How can I be sure if I'm alive or if I'm dead?
 There must be an evil demon that is pleased to hear my cries
 Corrupting and seducing me to believe in all its lies
 I shall no more be deceived by what remains impure
 I will fight the doubt and in the doubt I will be sure
 1) Evidence:
 Only accept the undeniable proof
 2) Analysis:
 Dissect the fact to find within the truth
 3) Synthesis:
 Put the pieces together, side by side
 4) Remembrance:
 Nothing to omit, nothing to hide
 I walk masked
 Through the valleys of ignorance mist
 I doubt
 And that's the only reason why I exist
 I walk masked
 And face this nasty urge to believe
 I doubt
 I think, I am, I meditate, I live
 Cogito ergo sum
 Cogito ergo sum
 (sum res cogitans)
 Cogito ergo sum
 Cogito ergo sum
 (sum res cogitans)
 No evil
 Shall hide
 The Truth
 Free Will
 Shall be
 The only law
 I think,
 I am,
 I have a choice:
 I believe!
 Res cogitans
 Res cogitans
 Res cogitans