Controversies and mysteries
The possibility of drug use
Many people have interpreted the encounters and events in the Alice books as hallucinations, usually noting the drinking of tea, consumption of mushrooms and the hookah smoking caterpillar, as references to psychedelic substances. The suggestion of drug use made him extremely popular to the counterculture of the 1960s, often being utilized by drug users as a positive way of showing the mainstream that one of their most famous and highly regarded writers also used these forbidden substances.
However, there is no evidence that he ever abused drugs. It is true that the standard domestic painkiller of the time, laudanum, was in fact a tincture of opium and could produce a "high" if used in a large enough dose and that Dodgson, most historians would agree, probably used it from time to time, but again there is no evidence he ever abused it or that its effects had any impact on his work.
Dodgson had been groomed for the ordained ministry in the Anglican Church from a very early age and was expected, as a condition of his residency at Christ Church, to take holy orders within four years of obtaining his master's degree. However, he evidently became reluctant to do this. He delayed the process for some time but eventually took deacon's orders in December 1861. But when the time came a year later to progress to priestly orders, Dodgson appealed to the dean for permission not to proceed. This was against college rules, and Dean Liddell told him he would very likely have to leave his job if he refused to take orders. He told Dodgson he would have to consult the college ruling body, which would almost undoubtedly have resultedin his being expelled. However, for unknown reasons, Dean Liddell changed his mind and permitted Dodgson to remain at the college, in defiance of the rules. Dodgson never became a priest.
There is currently no conclusive evidence about why Dodgson rejected the priesthood. Some have suggested his stammer made him reluctant to take the step, because he was afraid of having to preach, but this seems unlikely given his willingness to take on other public performances (story-telling, recitations, magic lantern shows), and the fact that he did indeed preach in later life, even though not in orders. Others have suggested that he was having serious doubts about the Anglican church. It is known that he was interested in minority forms of Christianity (he was an admirer of FD Maurice) and "alternative" religions (theosophy). Dodgson was deeply troubled by an unexplained sense of sin and guilt at this time (the early 1860s), and frequently expressed the view in his diaries that he was a "vile and worthless" sinner, unworthy of the priesthood.
The missing diaries
At least four complete volumes and around seven pages of text are missing from Dodgson's 13 diaries. The loss of the volumes remains unexplained; the pages have been deliberately removed by an unknown hand. Most scholars assume the diary material was removed by family members in the interests of preserving the family name, but this has not been proven. All of the missing material, except for a single page, is believed to date from the period between 1853 (when Dodgson was 22) and 1863 (when he was 32).
Many theories have been put forward to explain the missing material. A popular explanation for one particular missing page (June 27, 1863) is that it might have been torn out to conceal the fact that Dodgson had proposed marriage on that day to the 11-year old Alice Liddell. However, there has never been any evidence to suggest this was so, and a paper that came to light in the Dodgson family archive in 1996 provides some evidence to the contrary.
The "Cut Pages in Diary" document
The "cut pages in diary" document, in the Dodgson family archive in Woking, UK.
This paper, known as the "cut pages in diary document", was compiled by various members of Carroll's family after his death. Part of it at least was presumably written at the time that some of the pages were being mutilated, as it offers a brief summary of two diary pages that are now missing, including the one for June 27, 1863. The summary for this page states that Mrs. Liddell told Dodgson there was gossip circulating about him and the Liddell family's governess, as well as about his relationship with "Ina", presumably Alice's older sister, Lorina Liddell. The "break" with the Liddell family that occurred soon after was presumably in response to this gossip. An alternate interpretation has been made regarding Carroll's rumored involvement with "Ina": Lorina was also the name of Alice Liddell's mother. What is deemed most crucial and surprising is that the entry seems to make it clear Dodgson's break with the family was not connected with Alice at all.
Migraine and Epilepsy
In his diary for the year 1880 Dodgson recorded experiencing his first episode of migraine with aura, describing very accurately the process of 'moving fortifications' that are a manifestation of the aura stage of the syndrome. Given this manifestation, it's possible that he chronically experienced the more common form of migraine, consisting simply of headache and nausea, but no real evidence exists either way, though several people have suggested the odd experiences Alice undergoes in the stories may have been inspired by migraine-like symptoms. Indeed a condition, Alice in Wonderland Syndrome, has been named after it. Also known as micropsia and macropsia, it is a brain condition affecting the way objects are perceived by the mind. For example, an afflicted person may look at a larger object, like a basketball, and perceive it as if it were the size of a mouse.
Dodgson also suffered a single attack of what he called an "epileptiform" seizure. Some have concluded from this he was a lifetime sufferer from this condition, but there is no evidence for it in any of his diaries or letters, and it would seem unlikely for this to be the case if he had indeed suffered regular seizures.