diff --git a/src/ast.rs b/src/ast.rs
index 65a3bf3..4935873 100644
--- a/src/ast.rs
+++ b/src/ast.rs
@@ -178,12 +178,12 @@ impl BinaryOperation
 pub struct Function
 {
 	pub declaration: std::rc::Rc<FunctionDeclaration>,
-	pub arguments: Vec<Box<Term>>,
+	pub arguments: Terms,
 }
 
 impl Function
 {
-	pub fn new(declaration: std::rc::Rc<FunctionDeclaration>, arguments: Vec<Box<Term>>) -> Self
+	pub fn new(declaration: std::rc::Rc<FunctionDeclaration>, arguments: Terms) -> Self
 	{
 		assert_eq!(declaration.arity, arguments.len(),
 			"function has a different number of arguments then declared");
@@ -307,12 +307,12 @@ impl Implies
 pub struct Predicate
 {
 	pub declaration: std::rc::Rc<PredicateDeclaration>,
-	pub arguments: Vec<Box<Term>>,
+	pub arguments: Terms,
 }
 
 impl Predicate
 {
-	pub fn new(declaration: std::rc::Rc<PredicateDeclaration>, arguments: Vec<Box<Term>>) -> Self
+	pub fn new(declaration: std::rc::Rc<PredicateDeclaration>, arguments: Terms) -> Self
 	{
 		assert_eq!(declaration.arity, arguments.len(),
 			"predicate has a different number of arguments then declared");
@@ -340,7 +340,7 @@ pub enum Term
 	Variable(Variable),
 }
 
-pub type Terms = Vec<Box<Term>>;
+pub type Terms = Vec<Term>;
 
 impl Term
 {
@@ -379,8 +379,7 @@ impl Term
 		Self::boolean(false)
 	}
 
-	pub fn function(declaration: std::rc::Rc<FunctionDeclaration>, arguments: Vec<Box<Term>>)
-		-> Self
+	pub fn function(declaration: std::rc::Rc<FunctionDeclaration>, arguments: Terms) -> Self
 	{
 		Self::Function(Function::new(declaration, arguments))
 	}
@@ -546,8 +545,7 @@ impl Formula
 		Self::Or(arguments)
 	}
 
-	pub fn predicate(declaration: std::rc::Rc<PredicateDeclaration>, arguments: Vec<Box<Term>>)
-		-> Self
+	pub fn predicate(declaration: std::rc::Rc<PredicateDeclaration>, arguments: Terms) -> Self
 	{
 		Self::Predicate(Predicate::new(declaration, arguments))
 	}
diff --git a/src/format/formulas.rs b/src/format/formulas.rs
index 194a8e2..98f928d 100644
--- a/src/format/formulas.rs
+++ b/src/format/formulas.rs
@@ -483,9 +483,10 @@ mod tests
 		Box::new(Formula::or(arguments.into_iter().map(|x| *x).collect()))
 	}
 
-	fn predicate(name: &str, arguments: Terms) -> Box<Formula>
+	fn predicate(name: &str, arguments: Vec<Box<Term>>) -> Box<Formula>
 	{
-		Box::new(Formula::predicate(predicate_declaration(name, arguments.len()), arguments))
+		Box::new(Formula::predicate(predicate_declaration(name, arguments.len()),
+			arguments.into_iter().map(|x| *x).collect()))
 	}
 
 	fn predicate_declaration(name: &str, arity: usize) -> std::rc::Rc<PredicateDeclaration>
diff --git a/src/format/terms.rs b/src/format/terms.rs
index 6212b13..406ef23 100644
--- a/src/format/terms.rs
+++ b/src/format/terms.rs
@@ -316,7 +316,8 @@ pub(crate) mod tests
 
 	pub(crate) fn function(name: &str, arguments: Vec<Box<Term>>) -> Box<Term>
 	{
-		Box::new(Term::function(function_declaration(name, arguments.len()), arguments))
+		Box::new(Term::function(function_declaration(name, arguments.len()),
+			arguments.into_iter().map(|x| *x).collect()))
 	}
 
 	pub(crate) fn function_declaration(name: &str, arity: usize) -> std::rc::Rc<FunctionDeclaration>
@@ -404,17 +405,17 @@ pub(crate) mod tests
 		constant("e")
 	}
 
-	pub(crate) fn abc() -> Terms
+	pub(crate) fn abc() -> Vec<Box<Term>>
 	{
 		vec![a(), b(), c()]
 	}
 
-	pub(crate) fn a1b1c1() -> Terms
+	pub(crate) fn a1b1c1() -> Vec<Box<Term>>
 	{
 		vec![constant("a1"), constant("b1"), constant("c1")]
 	}
 
-	pub(crate) fn a2b2c2() -> Terms
+	pub(crate) fn a2b2c2() -> Vec<Box<Term>>
 	{
 		vec![constant("a2"), constant("b2"), constant("c2")]
 	}
@@ -434,7 +435,7 @@ pub(crate) mod tests
 		variable("Z")
 	}
 
-	pub(crate) fn xyz() -> Terms
+	pub(crate) fn xyz() -> Vec<Box<Term>>
 	{
 		vec![x(), y(), z()]
 	}
diff --git a/src/parse/formulas.rs b/src/parse/formulas.rs
index 0d71675..979275f 100644
--- a/src/parse/formulas.rs
+++ b/src/parse/formulas.rs
@@ -642,9 +642,9 @@ mod tests
 		assert_eq!(predicate_remainder("s ( )"), "");
 		assert_eq!(predicate("s ( 1 , 2 , 3 )").declaration.name, "s");
 		assert_eq!(predicate("s ( 1 , 2 , 3 )").declaration.arity, 3);
-		assert_eq!(*predicate("s ( 1 , 2 , 3 )").arguments.remove(0), Term::integer(1));
-		assert_eq!(*predicate("s ( 1 , 2 , 3 )").arguments.remove(1), Term::integer(2));
-		assert_eq!(*predicate("s ( 1 , 2 , 3 )").arguments.remove(2), Term::integer(3));
+		assert_eq!(predicate("s ( 1 , 2 , 3 )").arguments.remove(0), Term::integer(1));
+		assert_eq!(predicate("s ( 1 , 2 , 3 )").arguments.remove(1), Term::integer(2));
+		assert_eq!(predicate("s ( 1 , 2 , 3 )").arguments.remove(2), Term::integer(3));
 		assert_eq!(predicate_remainder("s ( 1 , 2 , 3 )"), "");
 		assert_eq!(predicate_remainder("s ( 1 , 2 , 3 )"), "");
 		assert_eq!(predicate("s ( ), rest").declaration.name, "s");
diff --git a/src/parse/terms.rs b/src/parse/terms.rs
index df0eaa5..b329ad8 100644
--- a/src/parse/terms.rs
+++ b/src/parse/terms.rs
@@ -59,7 +59,7 @@ fn absolute_value<'i>(i: &'i str, d: &Declarations) -> IResult<&'i str, crate::T
 }
 
 pub(crate) fn function_or_predicate<'i>(i: &'i str, d: &Declarations)
-	-> IResult<&'i str, (&'i str, Option<Vec<Box<crate::Term>>>)>
+	-> IResult<&'i str, (&'i str, Option<crate::Terms>)>
 {
 	pair
 	(
@@ -82,11 +82,7 @@ pub(crate) fn function_or_predicate<'i>(i: &'i str, d: &Declarations)
 						tag(","),
 						multispace0,
 					),
-					map
-					(
-						|i| term(i, d),
-						Box::new,
-					),
+					|i| term(i, d),
 				),
 				preceded
 				(
@@ -485,8 +481,8 @@ mod tests
 		assert_eq!(term_as_function("s").declaration.arity, 0);
 		assert_eq!(term_as_function("s(1, 2, 3)").declaration.name, "s");
 		assert_eq!(term_as_function("s(1, 2, 3)").declaration.arity, 3);
-		assert_eq!(*term_as_function("s(1, 2, 3)").arguments.remove(0), Term::integer(1));
-		assert_eq!(*term_as_function("s(1, 2, 3)").arguments.remove(2), Term::integer(3));
+		assert_eq!(term_as_function("s(1, 2, 3)").arguments.remove(0), Term::integer(1));
+		assert_eq!(term_as_function("s(1, 2, 3)").arguments.remove(2), Term::integer(3));
 	}
 
 	#[test]
@@ -715,9 +711,9 @@ mod tests
 		assert_eq!(function_remainder("s ( )"), "");
 		assert_eq!(function("s ( 1 , 2 , 3 )").declaration.name, "s");
 		assert_eq!(function("s ( 1 , 2 , 3 )").declaration.arity, 3);
-		assert_eq!(*function("s ( 1 , 2 , 3 )").arguments.remove(0), Term::integer(1));
-		assert_eq!(*function("s ( 1 , 2 , 3 )").arguments.remove(1), Term::integer(2));
-		assert_eq!(*function("s ( 1 , 2 , 3 )").arguments.remove(2), Term::integer(3));
+		assert_eq!(function("s ( 1 , 2 , 3 )").arguments.remove(0), Term::integer(1));
+		assert_eq!(function("s ( 1 , 2 , 3 )").arguments.remove(1), Term::integer(2));
+		assert_eq!(function("s ( 1 , 2 , 3 )").arguments.remove(2), Term::integer(3));
 		assert_eq!(function_remainder("s ( 1 , 2 , 3 )"), "");
 		assert_eq!(function("s ( ), rest").declaration.name, "s");
 		assert_eq!(function("s ( ), rest").declaration.arity, 0);