It has been known that alcohol taken in small or large quantities can greatly affect both our body and mind.
According to Dr. Brinton, mental acuteness, accuracy of conception, and delicacy of the senses, are all so far opposed by the action of alcohol, as that the maximum efforts of each are incompatible with the ingestion of any moderate quantity of fermented liquid. Indeed, there is scarcely any calling which demands skillful and exact effort of mind and body, or which requires the balanced exercise of many faculties that does not illustrate this rule. The mathematician, the gambler, the metaphysician, the billiard-player, the author, the artist, the physician, would, if they could analyze their experience aright, generally concur in the statement, that a single glass will often suffice to take , so to speak, the edge off both mind and body , and to reduce their capacity to something below what is relatively their perfection of work.
The said statement refers to the fact that even a single glass or a bottle of any alcoholic drinks could cause our body and minds to be distracted and kept off its normal processes.
The perfect example for this is an accident that happened a few days ago in a highway, a bus driver avoids collision with a truck making the bus bump into a post. The incident killed 10 people including bystanders. The truck driver made it alive and according to his statement he had 1 bottle of beer before going on with his trip.
Even with one glass or bottle your perception and control over your senses is already affected.