Survival skills
A human being can survive an average of three to five days without the intake of water. The issues presented by the need for water dictate that unnecessary water loss by perspiration be avoided in survival situations. The need for water increases with exercise.
Waseda University
On October 21, 2007, Waseda University celebrated its 125th anniversary. Ōkuma often talked about the "125 years of life" theory: "The lifespan of a human being can be as long as 125 years. He will be able to live out his natural lifespan as long as he takes proper care of his health", because "physiologists say that every animal has the ability to live five times as long as its growth period. Since a man is said to require about 25 years to become fully mature, it follows that he can live up to 125 years of age." This theory propounded by Ōkuma was very popular and often referred to in the media of the time.