1929 · Alexander Fleming
On the Antibacterial Action of Cultures of a Penicillium
What this work is
A laboratory paper reporting that a mould contaminant on a staphylococcus culture plate had dissolved the colonies around it. Fleming grew the mould in broth, filtered it, and tested the filtrate against a range of bacteria, recording which were inhibited and which were not. He reports the filtrate did not harm white blood cells or animals, and suggests it as a tool for isolating certain bacteria in culture and possibly as an antiseptic for wounds.
Then and now
Fleming showed that broth from a mould stopped and dissolved some bacteria on a plate. Medicine made him the founder of antibiotics, the drug side of germ theory, which treats bacteria as the cause of disease. His plates showed bacteria dissolving, not bacteria causing disease, and nobody has seen that.
Verdict
SCIENTIFIC
The work follows the scientific method and does not operate inside a theoretical framework. The verdict is scientific.
1·This work · no theoretical framework
SCIENTIFIC
Follows the scientific method. No theoretical framework attached.
2·Paradigm · Basic Epidemiological Comparison
NOT APPLICABLE
No theoretical framework. The study verdict decides.
How the verdict is decided
This work does not operate inside a theoretical framework. Using hospital records, billing codes, or diagnostic names as labels on visible events is not the same as depending on that framework. The verdict is the work methodology score alone.
1·This work
Did this work test its claim with methods that are independent, falsifiable, and non-circular?
SCIENTIFIC
This study claims that a broth in which a common mould has grown contains a substance, which he calls penicillin, that stops growth of and dissolves many common bacteria, and can be used to isolate influenza bacilli from mixed cultures. All three tests pass.
Independently Verifiable
Pass
The observation is the plate itself: colonies you can see either grow or dissolve, and no germ theory is needed to watch broth turn from cloudy to clear.
Falsifiable
Pass
If mould broth had left the staphylococcus streaks growing right up to the furrow, the claim would have been falsified, and his own tables show several microbes scored exactly zero.
Non-Circular
Pass
The mould broth was tested against broth that never touched mould, and against other moulds' broths, so the comparison was built without assuming the answer.
Why
The plate is the observation: colonies grow or dissolve where anyone can see them. Several microbes scored zero in his own tables, and broth that did nothing would have killed the claim. Mould broth was compared with plain broth and with other moulds' broths, so nothing assumed the answer.
2·Paradigm · Basic Epidemiological Comparison
The three tests do not apply. There is no theoretical framework.
NOT APPLICABLE
Why
This work does not depend on a theoretical framework for its result. The method is mixing a liquid with bacteria on a plate and watching what grows. Colonies, clearing zones, and cloudy or clear broth are events in the dish. The names of the microbes are labels on those events; drop the labels and the counts of growing versus dissolved colonies stay the same. The comparisons, mould broth against plain broth and against eight other moulds' broths, mean the same thing to someone who rejects every theory of infection. The disease claims sit downstream in later work; this paper's claim is about dissolution in a dish, and that claim stands or falls on what a stranger can see on the plate.
From the work
It was noticed that around a large colony of a contaminating mould the staphylococcus colonies became transparent and were obviously undergoing lysis (see Fig. 1).
Of these it was found that only one strain of penicillium produced any inhibitory substance, and that one had exactly the same cultural characters as the original one from the contaminated plate.
The inhibition can then readily be seen by noting the opacity of the broth.