2.10. Historical interlude: Sophus Lie 29
young minds, and one will have an excellent wine after the liquors
have settled a bit”. German mathematicians were less impressed.
Weierstrass believed that Lie’s theory lacked rigor and had to be re-
built from the foundations, and Frobenius labeled it a “theory of
methods” for solving differential equations in a roundabout way, in-
stead of the natural methods of Euler and Lagrange [22, pp. 186,
188–189].
Students flocked to Lie’s lectures on his own research, but this
only exacerbated his heavy teaching load at Leipzig 8–10 lectures
per week compared to the leisurely pace of his work in Christia-
nia. An outdoor man, who was used to weeks-long hikes in Norway,
Lie felt homesick, longing for the forests and mountains of his native
country. All this began taking its toll on Lie. Most importantly, he
felt underappreciated and became obsessed with the idea that others
plundered his work and betrayed his trust. His relations with col-
leagues gradually deteriorated, particularly with those closest to him.
He broke with Engel and eventually with Klein. Lie felt that his role
in the development of the Erlangen Program was undervalued, and he
publicly attacked Klein, claiming, “I am no pupil of Klein, nor is the
opposite the case, although this might be closer to the truth. I value
Klein’s talent highly and will never forget the sympathetic interest
with which he has always followed my scientific endeavors. But I do
not feel that he has a satisfactory understanding of the difference be-
tween induction and proof, or between a concept and its application”
[56, p. 371]. Whoever was right in this dispute, Lie’s public accu-
sations against widely respected and influential Klein reflected badly
on Lie’s reputation.
Eventually Lie suffered a nervous breakdown and was diagnosed
with “neurasthenia”, a popular mental disease dubbed the “American
Nervousness”, or “Americanitis”. Its cause was ascribed to the stress
of modern urban life and the exhaustion of an individual’s “nervous
energy”. Lie spent some months in the supposedly less stressful envi-
ronment of a psychiatric clinic and upon some reflection decided that
he was better off in his mathematics department. His mathemati-
cal abilities returned, but his psyche never fully recovered. Rumors
Previous Page Next Page