“Nothing is so difficult as not deceiving oneself.”

“It is so easy to convince others; it is so difficult to convince oneself.”

“In love, one always begins in deceiving oneself, and one always ends in deceiving others.”

“To deceive oneself is worse than to deceive others." These harsh words pierced me to the core.”

“Nothing is needed more than truth, and in relation to it everything else has only second-rate value."This unconditional will to truth—what is it? Is it the will not to allow oneself to be deceived? Or is it the will not to deceive? For the will to truth could be interpreted in the second way, too—if only the special case "I do not want to deceive myself" is subsumed under the generalization "I do not want to deceive." But why not deceive?But why not allow oneself to be deceived?Note that the reasons for the former principle belong to an altogether different realm from those for the second. One does not want to allow oneself to be deceived because one assumes that it is harmful, dangerous, calamitous to be deceived. In this sense, science would be a long-range prudence, a caution, a utility; but one could object in all fairness: How is that? Is wanting not to allow oneself to be deceived really less harmful, less dangerous, less calamitous? What do you know in advance of the character of existence to be able to decide whether the greater advantage is on the side of the unconditionally mistrustful or of the unconditionally trusting?”

“The truest way to be deceived is to think oneself more knowing than others.”