The Digestive Canal Represents A Tube Passing

The Sun-paul Must Consider Only One Thing: What Is The Relation Of This Or That External Reaction Of The Animal To The Phenomena Of The External World?

When The Dog Is Repeatedly Teased With The Sight Of Objects Inducing Salivary Secretion From A Distance, The Reaction Of The Salivary Glands Grows Weaker And Weaker And Finally Drops To Zero.

It Is Still Open To Question Whether Psychology Is A Natural Science, Or Whether It Can Be Regarded As A Science At All.

Do Not Become Archivists Of Facts. Try To Penetrate To The Secret Of Their Occurrence, Persistently Search For The Laws Which Govern Them.

Possibilities Are Like The Wings Of Birds; They Allow Man To Soar And To Climb To The Heavens. And Facts Are Like The Atmosphere Against Which Those Wings Must Beat, And Without Which The Soaring Bird Will Surely Plummet Back To Earth.