= Solution
\b[The historical arguments rested on similarities of cellular origin, degeneration and tissue reaction; they did not establish that <tuberculosis>, <cancer> and <inflammation> were one disease.] The question asks for the arguments advanced, so their evidential force must be separated from their historical importance.
First, <microscopy> revealed <biological cells> and <cell nuclei> in all three lesions. An older theory made morbid cells arise in an exuded formative fluid; <cellular pathology> sought their origins in pre-existing <tissue>. <William Turner>'s 1863 lecture explicitly compared the origins of corpuscles in <pus>, <cancer> and tubercle, but acknowledged their later divergence and unexplained specific characters. A common cellular origin could therefore suggest a relationship without establishing identity.<The present aspect of the doctrine of cellular pathology by William Turner>[Opening statement of purpose; pp. 896–897, origin and subsequent divergence]{ref}
Second, microscopic particles thought specific to tubercle could resemble shrunken <biological cells>, free <cell nuclei> and degenerated products in malignant or inflammatory lesions. Yellow caseous material was also not uniquely tuberculous. The 1860 year-book records the argument that so-called yellow tubercle could be the outcome of degeneration rather than a specific material already present in <blood>. This weakened the claim that the appearance of the end product alone established a separate deposited substance.<A Year-book of medicine, surgery and their allied sciences (1860)>[General Pathology and Symptomatology, p. 135, lack of a diagnostic tubercle corpuscle and tuberculoid metamorphosis]{ref}
Third, inflamed, injured or ulcerated regions can show exuberant growth, increased vascularity and infiltrating <leukocytes>. A <tumour> can itself ulcerate and become inflamed; a tuberculous focus can provoke surrounding <inflammation> and scarring. Such anatomical continuity offered an argument for a connection, but several explanations fit it: the inflammatory reaction might cause some changes, respond to the primary lesion, or merely coexist with it. A section containing all these features does not by itself identify their temporal order.
The correct assessment distinguishes \b[shared cellular responses from shared cause]. Modern <tuberculosis> involves an infectious organism and a host response that can include <granulomas> and <caseous necrosis>. Modern <cancer> involves malignant cellular growth with disease-specific molecular and tissue features. <Inflammation> is a response to diverse injuries and infections, not automatically an incipient <cancer> or a tubercle. Modern <inflammation> also commonly recruits <leukocytes> from circulating <blood>, so the historical proposal of universal local connective-tissue origin was itself incomplete. <Histology> must retain viable margins and tissue architecture rather than comparing only amorphous debris.
There is nevertheless a real modern connection between persistent <inflammation> and some <cancers>: chronic inflammatory processes can damage <DNA> and alter the environment in which <biological cells> proliferate. That supports particular causal pathways, not universal identity, and it does not mean that an ordinary inflammatory lesion inevitably becomes malignant.<Chronic Inflammation by the National Cancer Institute>[Inflammation, chronic persistence and DNA damage]{ref} \b[The strongest historical insight was a common cellular basis of pathology; the overreach was to infer a common disease from a common reaction or a similar degenerated product.]
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