Ethical speculation, as thus understood, must be concerned with psychological inquiries--inquiries in regions where the vague doctrines of common sense have not yet crystallized into scientific coherence; we must therefore proceed with caution. The contention between materialist and idealist is irrelevant to our discussion. The fact that mechanical processes underlie all mental process does not make the latter the less a fact; nor can the mechanical statement ever supersede the psychological statement. The proposition that hunger makes men eat will express truth, whatever material implications are involved in the statement. Conduct is determined by feeling; we fly from pain, we seek pleasure; life is a continuous struggle to minimize suffering and lay a firm grasp upon happiness. "Good" means everything that favors happiness, and "bad" everything that is conducive to misery; nor can any other intelligible meaning be assigned to the words. The difficulty of proving these propositions lies in the fact that they are primary doctrines, for proof of which we must appeal to the direct testimony of consciousness. But critics oppose, not so much the propositions themselves, as certain supposed implications. By pain and pleasure is here meant every conceivable form of agreeable or disagreeable feeling. The assertion that conduct is determined by pain and pleasure is not meant as a denial that it is also, in some sense, determined by the reason; but a state of consciousness which is neither painful or pleasurable cannot be an object of desire or aversion. The reason is often contrasted with the feelings in its determination of conduct, the reasonable man being defined as one who, instead of being the slave of immediate impulse, is capable of adapting means to ends and following, thus, courses of conduct not in themselves agreeable but promising a greater total of happiness. The fact is, however, that all happiness that determines the will is future; conduct is determined, in every case, not by a future feeling of pleasure, which, as future, does not yet exist, but by present feeling. It is therefore more accurate to say that conduct is determined by the pleasantest judgment than to say that it is determined by the judgment of what is pleasantest. The intention of the agent is defined by the foreseen consequences of his conduct; his end is defined by that part of the foreseen consequences which he actually desires; and the end defines the motive, that is, the feeling, which actually determines conduct. The pleasantest end is adopted because the foretaste of the pleasure is itself pleasurable. The intellect and the emotions are in reality related as form and substance, and cannot be divided.