In this age of science, the attention and interest of the universe have been largely focussed on the marvellous achievements of the human intellect. Discoveries, inventions, advanced methods and great strides of progress in countless directions are the boast and pride of modern times. There is no disputing this, nor is there any doubt but that a great wave of scientific accomplishment, which was somewhat slow in developing, has, within the last two generations, suddenly assumed the most stupendous and bewildering proportions. The railroad and the automobile; the telephone and electric light; the airplane, phonograph, moving picture; anti-septic surgery and the germ theory of disease; the dreadnought, the submarine and wireless telegraphy;--these are but a few striking examples of the hundreds and thousands of achievements which the intellect has been able to accomplish in a comparatively short space of time. No wonder that we hear and read on all sides such constant and confident reference to the "advancement of science," the "progress of humanity," and the bewildering resourcefulness of man's brain. All those achievements are objective and impersonal; they concern the comforts and welfare, of each and every one of us, to a greater or less extent, but in a purely material and general way. When we turn to the personal life of the individual and consider his acts and motives, subjectively, we find that the role played by the intellect is almost equally important. As we have seen in our previous discussions, the intellect has a say in nearly everything we do or think of doing. It enquires into the cause, and considers the effect, and passes judgment, for or against, in accordance with the dictates of its reason. If a certain instinct within us, which may be purely animal, has a need for food or water, the intellect recognizes and approves the need; but if the food and water set before us is poisonous or unfit, it is the intellect which determines that and overrules the instinct. If another instinct, or impulse, prompts us to set fire to a house, or jump out of a window, the intellect decides that such an act would be unreasonable and forbids us to do so. It frequently happens that two or more of our instincts, inclinations, desires, are opposed to each other. I want to eat my apple now; I want to keep it to eat at the ball-game; and I want to trade it for Tim's lignum-vitae top. In such a case, it is the intellect which considers the advantages and disadvantages of each and announces its decision. If it is a healthy intellect, in good control, it will enforce its decision, too; but even if it isn't, and an unruly impulse proves too strong to be denied, that won't prevent the intellect from pointing out the mistake that is being made and keeping it in memory for future reference.