Faith in a holy cause is to a considerable extent a substitute for lost faith in ourselves. Eric Hoffer
There is not only a close analogy between the operations of the mind in general reasoning and its operations in the particular science of Algebra, but there is to a considerable extent an exact agreement in the laws by which the two classes of operations are conducted. George Boole
We should note that this latter type of shift was successfully amplified to a considerable extent by Russian physicists using the intense light of a ruby laser whose wavelength is close to that of a transition of the potassium atom. Alfred Kastler