You cannot go on 'explaining away' for ever: you will find that you have explained explanation itself away. You cannot go on 'seeing through' things for ever. The whole point of seeing through something is to see something through it.

You can't know, you can only believe - or not.

We are always falling in love or quarreling, looking for jobs or fearing to lose them, getting ill and recovering, following public affairs. If we let ourselves, we shall always be waiting for some distraction or other to end before we can really get down to our work. The only people who achieve much are those who want knowledge so badly that they seek it while the conditions are still unfavorable. Favorable conditions never come.

You cannot run a business, or anything else, on a theory.

The knowledge of the theory of logic has no tendency whatever to make men good reasoner.

It has no ability to develop new knowledge through hypothesis testing, modification of the original theory based on experimental results and renewed testing through more refined experiments that yield still more refinements and insights,