It is a matter of very great importance for the user of tobacco that he should have clear information regarding the beneficial and harmful effects of tobacco on the human mind and body. There are very few matters which have been the subject of such varied opinions; such exaggeration and misconception. Those who are opposed to the use of tobacco have not hesitated to ascribe to it every form of evil, physical, mental and moral. Insanity, epilepsy, cancer, malignant throat disease, blindness, heart disease and a host of other diseased conditions are traced to tobacco smoking by its enemies. On the other hand the users of tobacco are scarcely less vehement in holding that no harmful effects follow, but ascribing all kinds of virtue as resulting from its use. It is not our object in this chapter to justify or recommend the use, or to advise the avoidance of tobacco; we think it is a matter that the individual should decide for himself. Moreover, we think that no general rules governing all cases can be laid down, but that each individual must judge for himself whether the use of tobacco is justified in his own particular case or not, taking into consideration all the circumstances that affect him. The important thing is that he should possess clear and correct information with regard to the effects of tobacco as far as such have been scientifically determined; and from the observation of its effects on his own organism to determine whether in his own case the practice is beneficial or otherwise and to what extent it may be pursued if he desires to smoke. We, therefore, purpose to submit the facts which have been determined by the most careful scientific investigators and others of high standing, who, from their experience in the investigation of the causes of disease, are best qualified to offer opinions which may be accepted as authoritative.