A Scientific Man Ought To

I Hate A Barnacle As No Man Ever Did Before, Not Even A Sailor In A Slow-sailing Ship.

After My Return To England It Appeared To Me That By Following The Example Of Lyell In Geology, And By Collecting All Facts Which Bore In Any Way On The Variation Of Animals And Plants Under Domestication And Nature, Some Light Might Perhaps Be Thrown On The Whole Subject.

But Then With Me The Horrid Doubt Always Arises Whether The Convictions Of Man's Mind, Which Has Been Developed From The Mind Of The Lower Animals, Are Of Any Value Or At All Trustworthy. Would Any One Trust In The Convictions Of A Monkey's Mind, If There Are Any Convictions In Such A Mind?

Nothing Is Easier Than To Admit In Words The Truth Of The Universal Struggle For Life, Or More Difficult--at Least I Have Found It So--than Constantly To Bear This Conclusion In Mind.

It Is Certain That There May Be Extraordinary Mental Activity With An Extremely Small Absolute Mass Of Nervous Matter: Thus The Wonderfully Diversified Instincts, Mental Powers, And Affections Of Ants Are Notorious, Yet Their Cerebral Ganglia Are Not So Large As The Quarter Of A Small Pin's Head. Under This Point Of View, The Brain Of An Ant Is One Of The Most Marvelous Atoms Of Matter In The World, Perhaps More So Than The Brain Of A Man.