Certainly every glass of beer has an influence on the cells of the brain and on the mind; so has every cup of tea or coffee, every bit of work and every amusement, every printed page and every spoken word. Is it certain that the influence is harmful because an overdose of the same stimulants is surely poisonous? Boiling water is most dangerous for the body on account of its strong heat: is a bath in lukewarm water therefore also harmful? To climb Mount Blanc would overtax my heart: is it therefore inadvisable for me to climb the two flights to my laboratory? Of course, under certain conditions it might be wise to take account of the slightest influences. Without being harmful, they might be unsuited to a certain mental purpose. If I were to take a glass of beer now in the morning, I should certainly be unable to write the next page of this essay with the same ease; the ideas would flow more slowly. But does that indicate that I did wrong in taking last night, after a hard day's fatiguing work, a glass of sherry and a glass of champagne at a merry dinner-party, after which nothing but light conversation and music were planned for the rest of the evening? Of course, alcohol before serious intellectual work disturbs me; but hearing a hurdy-gurdy in the street or thinking of the happy news which a letter has just brought to me, or feeling angry over any incident, disturbs me just as much. It is all the same kind of interference; the brain centers which I used for my intellectual effort are for a while inhibited and thus unfit for the work which I have in hand. When the slight anger has evaporated, when the pleasurable excitement has subsided, when the music is over, I can gather my thoughts again, and it is arbitrary to claim that the short blockade of ideas was dangerous, and that I ought to have avoided the music or the pleasure or the wine. Of course, if we consider, for instance, the prevention of crime, we ought not to forget that some even of these slight inhibitions may facilitate a rash, vehement deed and check cool deliberation. In times of social excitement, therefore, alcohol ought to be reduced. But again this same effect, as far as the temperate use of alcohol is in question, may result from many other sources of social unrest. The real danger begins everywhere with intemperance: that is, with a lack of that self-discipline which is not learned but lost under the outer force of prohibition. _The Case Psychologically_