No general rule satisfying reasonable constraints can be devised that transforms any set of individual preferences into a rational social preference (Arrow's impossibility result).
# Rational
A rational person is someone who makes decisions based on logic and evidence rather than emotions or hunches. Rational thinking means carefully considering the facts, weighing pros and cons, and coming to conclusions that make sense. It's the opposite of acting impulsively or based on feelings alone.
Reasonable constraints(as the conditions Arrow's theorem applies to)
Fair and sensible rules that we think any good voting or decision-making system should follow, such as respecting everyone's votes equally or not rigging the outcome in favor of one person.
social preference(used in political philosophy and economics)
What a group or society should prefer or choose, based on combining all the individual people's preferences.
Other arguments question the coherence of the idea of intrinsically fair collective decision making processes. For instance, social choice theory questions the idea that there can be a fair decision making function that transforms a set of individual preferences into a rational collective preference. The core objection is that no general rule satisfying reasonable constraints can be devised that can transform any set of individual preferences into a rational social preference. And this is taken