Eratosthenes's only tools were sticks, eyes, feet, and brains; plus a zest for experiment. With those tools he correctly deduced the circumference of the Earth, to high precision, with an error of only a few percent. That's pretty good figuring for 2200 years ago.
We cannot see outside what we are not inside. The universe is to us what the huge engine is to the miniature engine; and indication of any error in the tiny engine leads us to imagine trouble in the huge one.
There is only one inborn erroneous notion ... that we exist in order to be happy ... So long as we persist in this inborn error ... the world seems to us full of contradictions. For at every step, in great things and small, we are bound to experience that the world and life are certainly not arranged for the purpose of maintaining a happy existence ... hence the countenances of almost all elderly persons wear the expression of ... disappointment.
Indeed the reasoned criticism of a prevailing belief is a service to the proponents of that belief; if they are incapable of defending it, they are well advised to abandon it. This self-questioning and error-correcting aspect of the scientific method is its most striking property.
I would just like to remember some words of St. Francis of Assisi which I think are really just particularly apt at the moment. 'Where there is discord, may we bring harmony. Where there is error, may we bring truth. Where there is doubt, may we bring faith. And where there is despair, may we bring hope.
We early arrive at the great discovery that there is one mind common to all individual men: that what is individual is less than what is universalthat error, vice and disease have their seat in the superficial or individual nature.
Without scheming to do wrong, or to make others unhappy, there may be error and there may be misery. Thoughtlessness, want of attention to other people's feelings, and want of resolution, will do the business.
They (i. e., the Pythagoreans) did not advocate the free confrontation of conflicting points of view. Instead, like all orthodox religions, they practised a rigidity that prevented them from correcting their errors.
Even the good artisans fell into the same error as the poets; because they were good workmen they thought that they also knew all sorts of high matters, and this defect in them overshadowed their wisdom.
And so, onwards... along a path of wisdom, with a hearty tread, a hearty confidence.. however you may be, be your own source of experience. Throw off your discontent about your nature. Forgive yourself your own self. You have it in your power to merge everything you have lived through- false starts, errors, delusions, passions, your loves and your hopes- into your goal, with nothing left over.