Charles Bonnet

Charles Bonnet ( born March 13, 1720 in Geneva, † May 20 1793 in Genthod ) was a Swiss naturalist and philosopher in the Enlightenment. To him the discovery of parthenogenesis goes back.

Life and work

Biological research

Bonnet studied law, dealt next with scientific studies. Already at the age of 20 he wrote his study of the propagation of aphids without fertilization and described for the first time parthenogenesis. He then worked with Trembley on the polyps, and made observations on the respiration of caterpillars and butterflies and the construction of the tapeworm.

Bonnet suspected that microorganisms not - as John Turberville Needham (1713-1781) and Leclerc claimed - by spontaneous generation ( abiogenesis ) originated in sealed containers with meat broth, but by "invisible openings " could get into the vessels used. As a very early proponent of the theory of evolution, he accepted that nature always brings new designs, of which the monkey, for example, was the last attempt before the people.

Charles Bonnet is the first to describe the eponymous medical syndrome of Charles Bonnet syndrome: After his grandfather Charles Lullin at the age of 77 years at a clouding of the lens ( cataract ) was operated on, where he eventually became blind, he years later got vivid hallucinations of men and women, carriages and houses. He knew he was hallucinating and these things do not really exist. Bonnet realized that the brain of his grandfather produced the hallucinations, because this was missing the charm of the outside world. In his later life Charles Bonnet ill finally even to the syndrome described by him.

The " palingenesis Philosophique " from 1769

As an eye illness made ​​it impossible for him more microscopic observations, he began with speculative research, and he dealt in particular with Christianity. He wrote a treatise on the life after death ( Idées sur l' état ​​futur of êtres vivants, ou palingenesis Philosophique, Geneva 1769), the Arts and Humanities of Johann Kaspar Lavater under the title examination of the evidence for Christianity ( Zurich 1771) partially into German was translated. Lavater dedicated the treatise Moses Mendelssohn to move him to refute or move over to Christianity. The irritated response Mendelssohn led the reconnaissance Bonnet, to publicly distance of Lavater.

After Bonnet had been from 1752 to 1768 Member of the Grand Council of Geneva, he retired to his estate Genthod on Lake Geneva.

Philosophical empiricism

Bonnets philosophy was an empiricism. With John Locke and Etienne Bonnot de Condillac he derived all ideas of sensations that arise in the soul by oscillation of the brain fibers, conversely, all emanating from her movements are caused by such. The process itself, such as the brain or the soul acts upon that this remains a mystery. Now that the soul, though even immaterial, without connection with an organic substance ( one even if there is such a fine body ) is not virtue to think, he concludes that it would either not or only continue in conjunction with a new body, one by itself the way this continuance but could not imagine.

Memberships / Awards

In 1764, Bonnet was elected a member of the Scholars Academy Leopoldina.

Other works

  • Traité d' Observations sur quelques espèces insectologie ou de vers d' eau douce, qui coupe par morceaux, deviennent autant d' animaux complets (Paris 1745) ( digitization e- ) doi: 10.3931/e-rara-9827. Translation of Johann August Ephraim Goeze: Essays from the Insektologie. 1773
  • Vol 1, Vol 2
  • Vol 1, Vol 2