tolerance

Tolerance is the willingness to allow the existence of opinions, beliefs, or practices one disagrees with. The term appears in social, scientific, and technical contexts to denote acceptance or value limits.

In political and social philosophy, tolerance protects freedom of expression and minority rights while drawing lines to prevent harm. The paradox of tolerance argues that a tolerant society may need to resist intolerant ideas to survive.

In psychology and everyday life, tolerance also refers to the capacity to endure discomfort, delay gratification, or withstand stressful situations. Tolerance can grow with experience and coping strategies.

In medicine, drug tolerance is a reduced response to a substance after repeated use, requiring higher doses. Mechanisms include pharmacokinetic changes and pharmacodynamic shifts; cross-tolerance and tachyphylaxis can occur.

Immunology defines immune tolerance as non-reactivity to specific antigens, especially self-antigens. Central tolerance occurs in the developing thymus or bone marrow; peripheral tolerance involves regulatory cells and mechanisms that curb reactivity.

In engineering, tolerance is the permissible deviation from a nominal value in dimensions or performance, reflected in tolerance grades that influence manufacturing and assembly.

Biological tolerance describes the range of environmental conditions an organism can endure, such as temperature or salinity, shaping habitat and survival.

Across fields, tolerance combines acceptance of difference with practical limits to ensure safety, order, or function, and it can be cultivated through policy, education, and experience.