---
title: "minimumGrade(forFacts:)"
framework: gameplaykit
role: symbol
role_heading: Instance Method
path: "gameplaykit/gkrulesystem/minimumgrade(forfacts:)"
---

# minimumGrade(forFacts:)

Returns the lowest membership grade among the specified facts.

## Declaration

```swift
func minimumGrade(forFacts facts: [Any]) -> Float
```

## Parameters

- `facts`: An array of objects representing truths claimed or rejected by the rule system. For details, see the doc://com.apple.gameplaykit/documentation/GameplayKit/GKRuleSystem/facts property.

## Return Value

Return Value The lowest membership grade in the array of facts.

## Discussion

Discussion In fuzzy logic, this method is called the AND Zadeh operator, because it corresponds to the AND operator in Boolean logic. note: If a fact is not in the facts array, its membership grade for purposes of this operation is implicitly zero.

## See Also

### Related Documentation

- [facts](gameplaykit/gkrulesystem/facts.md)

### Drawing Conclusions from Facts

- [grade(forFact:)](gameplaykit/gkrulesystem/grade(forfact:).md)
- [maximumGrade(forFacts:)](gameplaykit/gkrulesystem/maximumgrade(forfacts:).md)