The Germans may be credited for teaching us, or trying to teach us, to distinguish "bread and butter" from what passes beyond, transcends bread and butter. With them the distinction is thoroughly ingrained, and comes to hand at a moment's notice. If I am to review in detail what may be considered the practical or applied departments of logic and psychology, I am in danger of trenching on their "bread-and-butter" region. Before descending, therefore, into the larder, let us first spend a few seconds in considering psychology as the pursuit of _truth_ in all that relates to our mental constitution. If difficulty be a stimulus to the human exertions, it may be found here. To ascertain, fix, and embody the precise truth in regard to the facts of the mind is about as hard an undertaking as could be prescribed to a man. But this is another way of saying that psychology is not a very advanced science; is not well stored with clear and certain doctrines; and is unable, therefore, to confer any very great precision on its dependent branches, whether purely speculative or practical. In a word, the greatest modesty or humility is the deportment most becoming to all that engage in this field of labour, even when doing their best; while the same virtues in even greater measure are due from those engaging in it without doing their best. It must be admitted, however, that the highest evidence and safeguard of truth is application. In every other science, the utility test is final. The great parent sciences--mathematics, physics, chemistry, physiology--have each a host of filial dependents, in close contact with the supply of human wants; and the success of the applications is the testimony to the truth of the sciences applied. Thus, although we may not narrow the sphere of truth to bread and butter, yet we have no surer test of the truth itself. Our trade requires navigation, and navigation verifies astronomy; and, but for navigation, we may be pretty confident that astronomy would now have very little accuracy to boast of. To come then to the practical bearings or outgoings of psychology, assisted by logic. My contention is that the parent sciences and the filial sciences should be carried on together; that theses should be extracted by turns from all; that the lights thus obtained would be mutual. I will support the position by a review of the subjects thus drawn into the metaphysical field. * * * * * [PROBLEMS OF EDUCATION.]