For
They encourage equality and global unity.
Against
They lack culture and real-life relevance.
Anonymous excerpts, translated where noted.
“There is a culture around Esperanto speakers.”
“Because it's fun and interesting and because people use it to travel, make friends, participate in international festivals, etc.”
“Esperanto is fundamentally useless.”
“It also suffers the critical mass problem, where a system can’t succeed until people use it, but people won’t use it until it succeeds.”