Reflect that nothing except the soul is worthy of wonder; for the soul, if it be great, naught is great.—Seneca, Letter 8.
Over half a decade ago I invited Peter Sloterdijk to a workshop; twenty-four days later, I inquired if the invite was received. I went ahead and planned the workshop without him. Not long before the workshop I heard from his 'assistent,' who was volunteered by Herr Prof. Dr. Sloterdijk to take his place. I felt bad for the 'assistent,' who confessed to having lack of time to prepare. I declined to put him on the program. But I did ask him to convey to Prof. Sloterdijk the thought that "he needs to realize this is no way to treat a colleague who (for example) may write his obituary one day."* (Not nice, admittedly, but it captured my outrage.) Much to my surprise, Sloterdijk answered the following week that there must have been a confusion because he had already written me a letter to inform me of his absence. After a round of apologies, we left it at that.**
By 'celebrity philosopher' I mean to convey a philosopher whose name is familiar beyond her own academic milieu; possibly her ideas and works are discussed not just in professional venues, but also in a wider context. So, I am not talking about somebody who offers a 'philosophy' to media-stars nor does a 'celebrity philosopher' have to possess mass fame. In our day, my old teachers, Daniel Dennett and Martha Nussbaum are paradigmatic celebrity philosophers. When I label somebody a ‘celebrity philosopher’ I do not intend to convey a judgment of quality one way or another.