We Do Not Know. We Can Only

Our Aim As Scientists Is Objective Truth; More Truth, More Interesting Truth, More Intelligible Truth. We Cannot Reasonably Aim At Certainty. Once We Realize That Human Knowledge Is Fallible, We Realize Also That We Can Never Be Completely Certain That We Have Not Made A Mistake.

No Rational Argument Will Have A Rational Effect On A Man Who Does Not Want To Adopt A Rational Attitude.

To Give A Causal Explanation Of An Event Means To Deduce A Statement Which Describes It, Using As Premises Of The Deduction One Or More Universal Laws, Together With Certain Singular Statements, The Initial Conditions ... We Have Thus Two Different Kinds Of Statement, Both Of Which Are Necessary Ingredients Of A Complete Causal Explanation.

In So Far As A Scientific Statement Speaks About Reality, It Must Be Falsifiable; And In So Far As It Is Not Falsifiable, It Does Not Speak About Reality.

The Initial Stage, The Act Of Conceiving Or Inventing A Theory, Seems To Me Neither To Call For Logical Analysis Nor To Be Susceptible Of It.