Sign language as harmful to deaf education

Sign language was treated as harmful to deaf children's speech, lip-reading and intellectual development, making pure oral instruction the institutionally preferred method of deaf education.

1 episode

Current understanding

Natural sign languages are full human languages and can provide deaf children with fully accessible linguistic input. When accessible from infancy, they are acquired on the same broad developmental timetable as spoken languages. Evidence does not support the claim that exposure to a sign language inherently damages spoken-language acquisition; delaying access to an accessible first language can instead produce language deprivation. Educational and communication approaches should be matched to the individual child rather than imposing a single modality.

Consequences and human impact

The 1880 Milan Congress gave international professional authority to pure oral education by declaring articulation superior to signs and simultaneous signing harmful to speech, lip-reading and precision of ideas. The resolutions were influential across deaf-education systems and contributed to the exclusion and devaluation of sign languages and deaf teachers. In 2010 the International Congress on the Education of the Deaf formally rejected the Milan resolutions.

How the consequences followed

The Milan Congress did not itself enact a worldwide legal ban on sign language. Its importance was professional and institutional: its resolutions supplied international authority for oralist policies subsequently adopted across many deaf-education systems.

The 2010 endpoint marks ICED's formal repudiation of its nineteenth-century resolutions, not the date oralism disappeared from every school or the date sign language became universally available.

The correction is not that speech, hearing technology or oral instruction are inherently harmful. The rejected proposition is that sign language itself impedes deaf children's linguistic or intellectual development and should therefore be systematically excluded.

160–4

Vote for the 1880 resolution declaring articulation superior to signs

150–16

Vote for the resolution preferring pure oralism over simultaneous speech and signs

130 years

Time between the Milan resolutions and their formal ICED repudiation in 2010

Quantitative figures are highlighted only when the cited evidence supports them. The scale of a related catastrophe is not automatically treated as a death toll caused solely by this belief.

Institutional episode

International — International Congress on the Education of the Deaf

1880–2010Officially endorsed

In September 1880 the Milan Congress declared articulation superior to signs and said combining speech with signs injured articulation, lip-reading and precision of ideas. Its resolutions gave international professional authority to pure oral education and were subsequently influential across deaf-education systems. In 2010 the 21st International Congress on the Education of the Deaf formally rejected the Milan resolutions, acknowledged their detrimental effects and called for respect for all languages and forms of communication.

Institutions

International Congress on the Education of the Deaf (ICED)

Documented consequences

International professional endorsement of pure oral instruction
Exclusion or devaluation of sign languages in many deaf-education programs
Exclusion or marginalization of deaf teachers in systems organized around oralism
Reduced access to fully accessible language for children who could not adequately access spoken instruction

Institutional machinery

At Milan in September 1880, an international congress of educators adopted resolutions declaring the “incontestable superiority” of articulation over signs and arguing that simultaneous speech and signs injured articulation, lip-reading and precision of ideas. The congress therefore preferred the pure oral method. Those resolutions did not possess legislative force by themselves, but they became an influential professional reference point for deaf-education institutions internationally. At the 2010 ICED in Vancouver, the congress formally rejected the Milan resolutions and acknowledged their detrimental effects.

Sources and what they establish

Report of the proceedings of the International Congress on the Education of the Deaf, Milan, 1880International Congress on the Education of the Deaf / Wellcome Collection
The Milan Congress, 1880 — resolutionsDeaf History Europe
Transcribes the congress resolutions and recorded votes, including 160–4 for the resolution declaring articulation superior to signs and 150–16 for preferring pure oralism to simultaneous speech and signs.
1880 Milan Congress records — Memory of the WorldWorld Federation of the Deaf
Rejection of ICED Milan decision embraced by deaf educators and leadersGallaudet University
Records the 19 July 2010 ICED statement formally rejecting the 1880 resolutions, acknowledging their detrimental effects and calling for respect for all languages and forms of communication.

Last reviewed: 24/08/2026